i highly recommend sombralabs for the receiver, if it will fit.
i have owned a 4 channel pico GWS, and now have 2 lepton6, 6 sl8, and 2 shadow7s (sl8 predecessor).
the GWS 4 channel receiver is smaller than the lepton6, but is a single conversion radio. in my SWM blueback, it was a very glitchy setup. an added bonus with the sombralabs is the programability of failsafes for all channels using their shadow programmer.
for a complete run-down on what is available from sombralabs: