I have the QYT KT-7900D which is a tri-band (140/220/440) rebranded version of the DB25 and the BTech UV-25X4 and it's fully supported by CHIRP. It's not a bad radio for the price, but it has some behaviors I don't like. If you're monitoring more than one channel, whenever any monitored channel breaks squelch, the radio goes to that channel and there's no way to leave it until the squelch closes. I don't care much for that. Also, it scans very slowly; so slowly that it's nearly useless. I ended up programming only channels in the 1.25 meter band and using it as a dedicated 1.25m radio. In that role, it works just fine, since only monitoring channels in one band means I get less unwanted traffic "trapping" me on a channel. As a dedicated GMRS radio, it should also work just fine. You'll probably want to only monitor no more than two channels at a time, though; the quad-watch can get overwhelming. If I were using it for GMRS (which may happen), I'd monitor a couple of my favorite repeaters and leave the other two channels set to something I might want to switch to but not continuously monitor.
It does output the advertised 25 watts, which is refreshing. The receive audio isn't the best, and I have to turn the volume pretty high to understand it. Transmit audio seems to be just fine, though. It receives about as well as my other radios. Overall, it's a decent radio for the price. For $90, I really can't complain. Interestingly, it's $11 cheaper than the DB25-G, at least on Amazon, although Radioddity offers some bundles which are less expensive than buying the QYT and accessories separately.