@jollysea Most of the time it just works. Using it with an external controller (either 8bitdo bluetooth, or Switch Pro Controller via Mayflash NS) is pretty smooth, but I've found no way to access the quick settings menu (the one that pops up if you press the right "..." button) - normal "STEAM" menu works fine.
Have to get up to push the button to turn it on!
Games seem to be upscaled from 720p to whatever resolution the external TV (FullHD / 4k) - but that might be a settings thing?
@noiob yah I know, I don't wanna, though - I sometimes game on my PC too, where I have an Xbox controller, so the position is more important than the letters on the buttons to me