I'm a scientist by training so not usually one to use hyperbole (especially where it feels click-baity in titles) but I really do mean it here: This is the best value quad I've reviewed so far this year. It is not the best long range, it is not the best free-style and it is not the best racer. But for those occasions where you are looking to fly in a small to medium park, empty office or commercial area out from your back yard which is 90% of my fling, this is the ideal tool for the job.
The HappyModel Sailfly-x is a "toothpick class" ultralight micro quadcopter. It has an all up weight of 38g without battery and can take 1s, 2s or 3s batteries. It is available with onboard FRSKY, FlySky or DSM reveivers or without a receiver where you can add crossfire or anything else. It is a fairly complete kit (see below) and is available for just $88 at full retail. Availability seems to be somewhat limited to Banggood at time of writing but my guess is that many retailers will pick this one up.
For this review I'll break down what is included, the specs, document differences from the stock betaflight and then cover off in the actual review performance on 2s, 3s, FPV performance and close with a summary and my recommendations. I'll also list spares and upgrade parts as the become available.
Specs and what this means