If you turn off WIFI before starting the emulators they will improve in frame-rate considerably. WIFI and BT are on the same chip and the controller is BT

NES.emu and Snes9x EX+ are the ones I have tested so far and are not super perfect, but good enough especially after turning wifi off. I tested other emulators for both and these were the best for the gamestick. Some games I played astyanax, ducktales, tmnt turtles in time, etc.
After playing for a few minutes with the controller in both emulators this is what I felt:
Buttons need to be press farther than standard presses, not too much difference, but noticeable in games that you need to constantly press a button.
Dpad is just ok
Joystick is just awful, huge dead zone IMO.
If they were going to call the thing gamestick, they should have paid a few more bucks for better controller hardware.
Wish there was a way to turn it off when the tv is off. I feel like it might consume too much power?