FrSky XM+ Ultra Mini SBUS Receiver, ONLY 1.6g
My standard FrSky RX, small and light -
This is the easiest RX to install ever. 5vdc/GND/Signal and it is up and running. RSSI is all I really felt I needed as I have an OSD that is giving me the flight data and full telemetry is not needed in my case. The board is super small and even on MICRO drones, it is easy to fit.
It's an obvious choice for racer quad. Number of channels is enough, simple 3-wire connection, light, full range. I had to flash receiver to get RSSI on channel 16. Telemetry is not needed if you have everything on your OSD. Maybe with simple 3-pin jst connector would be sometimes a little bit easier to maintain your quad, without resoldering.
Great Lightweight Minimalist Option
Great choice for a lightweight diversity capable receiver. No SmartPort/Telemetry thrills, but is a brilliant pairing on really light or really small FPV builds where a VTX (like the eachine VTX03) can't be controlled by it anyway. Really happy with mine - to get everything I want with the R-XSR is a bit more cost and a bit more weight anyway.
Great mini/micro Frsky receiver
For the price, by far one of the best Frsky receivers out there; of course non-telemetry, but FULL RANGE (about 1000m ground 4Km open air -no obstacles).