Well, so much for that. After having my RG350 for a few weeks now I turned it on a few minutes ago and the screen started going all rainbow-effect on me.
It was working fine an hour ago when I was playing a Genesis game. Turned it off to get something to eat, turn it on again and now the screen is bad. On firmware 1.5.1. I'll try reflashing the firmware again but that's probably not going to fix it, there's probably a cold solder joint somewhere on the board that finally gave up the ghost.
My GCW-Zero from 2013 is still fine after hundreds of hours of play but this "new and improved GCW-Zero" turns out to be a hunk of garbage after a few weeks.
Oh well, it was good while it lasted I guess. Once my PocketGo pre-order comes in, I'm done with Chinesium handhelds.
UPDATE: Put original micro-SD card with the shipped firmware in it and the screen is still bad. Into the drawer of broken crap it goes.