Diatone / SNT /JUSTAIR Q25 Micro FPV RC Car Review

The Diatone / SNT / JustAir Q25 Is a tiny RC car that is smaller than a matchbox and yet still has proportional steering, throttle and even front suspension. It is a follow up from the Diatone Q33 micro RC car released last year and offers a lot more features. It is available in regular version or FPV - a model with a small camera and video transmitter that send live first person view video back to goggles to immerse you in first person driving. Here I review the FPV version that includes everything you need to get running.

Last year Diatone, a well known brand in the quadcopter market, released their first RC car - the micro 1/76 scale Q33 that I reviewed here. As of September 2022 they have now released an update with a whole lot more features which build on the best micro RC car released so far. First of all just look at that body - the Datsun 240Z is my all time favourite classic so it's a pleasure to see it in tiny scale here, even if it is a caricature of the real thing. Before I get carried away though, lets see what is included:

Let's cover off the main things included first:

• The 1/76 scale Q25 car with Datsun 240z body. As you can see I have the FPV camera option with the cam/VTX mounted on top
• The transmitter that is covered in buttons and has an interesting offset steering wheel angle. Included is a single pre-installed 18650 li-ion cell.
• The FPV goggles with built in 5.8GHz diversity receiver, built in LiPo battery and DVR.
• USB cables for charging the car from a regular USB outlet
• A USB-C to USB-C adaptor stowed in the transmitter so you can charge the car directly from the transmitter
• 2 Antennae for the goggles
• Micro USB charging cable for the goggles
• AV output cable so you can playback your live video feed or DVR on a big screen - imagine sitting in your lounge driving with the TV displaying your FPV feed....
• 2 branded Key rings
• Manual in English and Chinese
• 4 large detailed stickers showing off the 240z design.

A Closer Look at the Car

Body. I need to mention this first because it is a highly detailed caricature of the beautiful Datsun 240Z, a classic Japanese sports car from the early 1970s. There are multiple colour options available including the patina look like I have, Gulf racing livery, Martini racing livery and the classic Datsun 240Z orange. The FPV camera on top is nicely enclosed but spoils the look somewhat although with it's cartoon-style you can't take it too seriously.

Steering and Throttle are both fully proportional meaning if you turn the wheel a little, the car turns a little and if you turn the wheel a lot, the car turns a lot. This is the same for the throttle. While we are on the throttle, this is powered by a very small brushed coreless motor similar to what we see on whoop-style quadcopters and ultralight foam RC planes. They tend to be fairly reliable. The drive for this car is a worm gear which offers a good reduction drive in a small space but you must NEVER turn the wheels by hand or by pushing along the ground, it will ruin the gearbox. Certainly something you need to be mindful of around little people.

Here you can see the micro USB-C port for chargin, the on off switch, the end can of the little motor and the proportional steering

Bearings. I've just found out this tiny car has bearings, at least in the rear drive shaft which is quite a surprise. This should help with efficiency and longevity of the moving parts. Not as big of an impact on a small car but a nice sign they are looking at the detail.

Suspension is real! On the front anyway with small coil springs. I doubt they do much but it's a nice idea. Wheels are solid rubber so strictly smooth surfaces only. They will grip on carpet.

Lighting is something we didn't have on the previous Q33 release but here on the Q25 it is something else, all being controller through the transmitter. The functions are:

• Indicators: Turn the steering wheel left and the rear lights indicate left and right for right.

• Brake lights: If you brake or reverse the brake lights will light up.

• Headlights: If you hit the head light button on the transmitter it will cycle through the headlight options... off, low and high

The circle switch cycles the headlight options. The switch to the right of this cycles the undercar light options below

Headlights on here

• ​​Underbody lighting: Ultimate bling! This will cycle through 6 underbody lighting colours as below (plus off of course). Click the image for a closer look.

The Transmitter is fairly small and light but is well featured as you can see. Steering is smooth and the foam covered wheel is nice. The angled steering wheels is unique and it comes off as look and working well. Throttle/brake trigger is smooth enough. There are discrete digital button for adjusting steering trims and buttons on the front for turning on headlights and underbody lighting. There is a dedicated button for turning the FPV camera and VTX on and off which is good for maximising battery life in case you are not using FPV. Lastly there is a multi-function button on the back which is not mentioned in the manual but I am hoping will allow for adjustment of steering dual rate.

The power switch is on the rear as are dedicated buttons for choosing 70% or 100% max throttle available. Finally there is a power outlet that allows you to charge the little car directly from the transmitter - the usb adaptor is included and has a stow port under the battery cover. Speaking of the battery cover, this contain a single 18650 Li-Ion cell which is included and should power the transmitter and car for roughly 90 years.

The FPV goggles are a basic white monocular unit and from my experience and comfortable and fit well. The have diversity reception meaning they switch to the strongest of 2 input signals. The have a built in lipo which is a handy feature but most surprisingly have a built in DVR - this means with a basic Micro SD card that you can record (and play back) your FPV drives. There is a lot of adjustability in terms of brightness, contrast etc. As mentioned earlier there is a composite video out cable meaning you can output the video signal to a screen or TV... Big screen FPV racing!!!

Lastly, like the video transmitter on the car, these default to 4 preset channels with good band separation for racing with up to more people. Note: you can access all 48 channels on standard analogue FPV bands if you unlock this function in the menu but I recommend against this if you are just using for the car.

Here are all the controls and ports for the goggles

Micro SD card for the DVR goes in here

Screen looks like this

Here are the menu options

Performance - Car

There is quite a bit going on here with a little car like this. First of all let's talk about how the car runs without using the goggles. It's no great. The weight of the camera on top of the car makes the power to weight ratio pretty poor so what little power it does have is blunted by the weight of the FPV camera and VTX on the roof. It's great that you can turn the VTX and camera off from the remote when not in use to save power but a shame you can't unplug it altogether when not in use. Top speed would be around 5-7km/h for this car. I can't put my GPS on to measure as the car is just too small!

Steering lock is too large which means this car either spins out or tips over easily depending on how much grip the surface offers. I believe the steering dual rate or end points can be adjusted with the multifunction button on this car (they allude to it in the manual for dual rate) but I'm yet to find the instructions published.

I found grip pretty poor on my hard floors but to my embarrassment, it's probably because they are a bit dirty. Carpet offers better grip but you would need a fairly short pile. It's very good on smoot asphalt or concrete.

Performance - FPV camera and goggles

Clearly there are a lot of compromises as a result of having the camera on the roof, so is it really worth it? Well, the FPV experience it much better than regular driving, lets see why.

Firstly, from what I see in the documentation, the video transmitter for the camera transmits at or below 25mW. This is appropriate for a car that has 20m or less control range because more power could cause bleed onto other frequencies and of course take more power from the already small battery that powers the car as well Transmission is very clear, especially since you will never be that far away from the car. Please note that on some documents it states that the VTX transmission power is 2W (2000mW) which is patently incorrect.

The goggles are surprisingly comfy and well featured. There is a large single LCD display behind a fresnel lens. These are cheap to make a very effective which make them great as beginner goggles, if a little dorky. Don't forget, we are playing with little toys here! The micro SD card-based DVR is really useful - you can record your exploring or racing as I've done below. Bear in mind the DVR is of lower video quality than what you actually see in the goggles, I've done a comparison video below.

Driving in FPV is a lot more fun that I was expecting. Just trundling around and exploring was really cool, especially because the car is so small and can fit under and through more that you would expect. As such, the opportunities for using it to mess with your family and co-workers are strong. I'm just waiting till the boss is away before I take it in to work! Certainly if you get the FPV model then this is the way to drive. It's just a shame it's so all or nothing.

Summary and Recommendations

The Diatone / SNT / JustAir Q25 is a fantastic looking micro RC car that is modelled on the classic Datsun 240Z and looks fantastic. It is a available as a regular model (car with transmitter) and a FPV model (car with camera and VTX mounted on top) with transmitter and FPV goggles. I reviewed the FPV model. The car is extremely well featured for something smaller than a hotwheels car - proportional steering and throttle; multiple light options with working brake lights and turn signals and even front suspension. In use however the FPV camera adds a lot of weight and brings the centre of gravity very high and so adversely affects handling and performance when driving it like a regular car. Driving it in FPV is much better though, thanks in a large part to the excellent budget goggles and clean signal sent from the video transmitter on the car. This is certainly the most fun way to drive this car.

If you are looking for a new style of toy to play with I can tentatively recommend this one but you do need to be aware of the impact the camera weight has. If you can work with that though this car is a lot of fun. If you wan't to drive it like a regular RC car (i.e. not as FPV) then I definitely recommend the non-FPV version.

UPDATE: Looks like this car will have a lot of parts support, with different coloured bodies, replacement transmitters and all other parts readily available. Here is the link for the manufacturer's web site

If you are looking to purchase, Banggood have the full range of bodies in FPV and non-FPV versions available here ​Diatone SNT JustAir Q25 1/100 2.4G FPV/RTR Micro RC Car

If you are looking for a discount on this car, I will post any coupon codes or flash sales for it over here on my coupons and discounts page. Remember buying from any of these links supports my page without any cost to you and is appreciated especially since I don't ask for money via patreon and the like. If you want to get involved in this discussion, feel free to join the QuadifyRC Facebook Group Here or like my page below​