I have one. Mind you, this is specifically about my 300eur aliexpress unit.

Good points: Display quality is great, better than 90% of modern infotainments. Backup cam. Waze, google maps etc. Mine had some small crappy sound amplifier, I couldn’t believe how good it works. The sound is better than 99% of cars I’ve driven in, and that’s with stock speakers. Changed the feel of the car, the stock m-ask and ccc units really date the car.

Bad points: Takes 20 seconds in the morning to boot up, then another 5-10 seconds for the phone to connect. Wired connection is great, wireless sometimes works and sometimes doesn’t. Stock optical loop connector is simply left unplugged, no optical loop, or anything, so it throws a code in diagnostics software. Microphone is garbage, utter garbage, and on mine external one I try to connect doesn’t work either. This is actually the worst thing about it since when the phone is connected to android auto you can’t even put the phone on speaker or do anything but answer it on the car unit and noone can hear anything you say. Almost a deal-breaker for me, almost. Stock Idrive control knob doesn’t work well in android auto mode, have to use the touch screen. Then again, you don’t need it often and usually stopped anyway so not a big deal Sound comes from AUX only, if you want to switch from aux to radio you have to exit the units “desktop” to the original one and do it there, same with climate control and service/fault screen. Not a big deal either.

All in all, I’m very glad I bought it. Besides the microphone stuff, everything else is great and I’d do it again.