Micro quads are great, you can fly smaller spots, they are quiet and less intimidating for other people that may be about. Until recently many have suffered from poor cameras by today's standards. AIO CMOS cameras were a game changer allowing FPV where it simply couldn't fit before but now their poor image quality (especially) light handling is being shown up by micro CCD cameras like the runcam swift micro 2 and foxeer arrow micro 2 and also the camera that is included with the HGLRC XJB F428 - TX20 - ELF . Additionally AIO cameras are limited to 25mW which simply doesn't offer enough range for the newer and more powerful brushless micros.
In order to make upgrading as simple as possible, Fullspeed (makers of the Leader 120 and Grasshopper 94) are selling the TX200 5.8G 48CH FPV Transmitter which screws to the back of your micro swift or arrow and protrudes no further than the plug on the back as you can see above.
The Leader 120 is my favourite micro and in my initial flight review I found the only chink it's armour was the camera image quality and VTX power. Below is the link to the tips and tricks section where I specifically mount it in the Leader 120: LEADER 120 CAMERA AND VTX UPGRADE
Considerations when installing worth thinking about for any quadcopter:
So is it an improvement? Oh yeah! Night and day! For the camera the image is so much clearer and I can focus it properly which was a real problem on my original camera. It handles light so much better and as with all CCD cameras the settings can be adjusted using the included remote. I can see everything especially going around and under trees which is my favourite type of flying. Not only that I found myself being able to fly much closer to sunset with full visibility.
For the vtx when I first connected it to my leader I used the flight controller BEC to wire it exactly as I had the original AIO camera. Unfortunately this resulted in diagonal lines which became worse to the point of breakup on high throtte. This tells me it is more sensitive to electrical noise that the AIO it replaced. The good news was this problem was solved by using battery voltage instead. This had the added benefit of taking load off the flight controller BEC (especially @ 200mW transmit power) but was inconvinient in that I had to solder additional wires to the VBAT pads. Once this was rectified, the VTX set to 25mW is actually much better than the AIO - a clearer signal over greater distance when flying without obstructions between VTX and receiver. Set to 200mW and wow! So much better range but more importantly the penetration through trees is superior. Now it is not dicey when I go behind and around large trees, there is minimal breakup compared to before where you rolled the dice every time a large tree came between you and the quad. In essence This means I can fly lower around trees rather than above for fear of losing VTX signal - way more fun! Changing the channel/band/power is comparable to other VTXs in that a single button quick press with change channel, 3-6s will change band and 6s+ will toggle power between 25mW and 200mW. Reading the channel can be a chore though - 1: because interpreting the small LEDs is challenging and 2: Being a piggyback vtx it will likely be mounted somewhere that the LEDs are obscured! The saving grace here is that Micros are typically flown solo as opposed to raced and so channel changing is not a particularly frequent occurence. Your own experience will dictate the importance here.
In conclusion the changing the AIO CMOS cam to the micro CCD cam (micro swift, micro arrow, HGLRC Elf) is an absolute game changer and other than the very smallest micro builds I will never go back to CMOS (runcam sparrow excluded). For the VTX, it is compact and tidy but was a bit disappointed in how sensitive it was to electrical noise on 5v. To be fair though, this may well have been the flight controller but wasn't apparent on the AIO. No issue whatsover running off VBat though with the upside of the VTX doing the work of the BEC rather than the flight controller. For a total package (micro CCD and TX200) this is a tidy little combo that is very handy for stashing the VTX in a covinient location in your quad rather than awkwardly added on top of your stack etc. It also makes it easy to transfer between quads.