A decent clone console
This console clone is one of the those console-on-a-chip clones, where MegaDrive /Genesis is actually just an emulator. It's compatible with decent range of games, and only the MegaDrive's later games have trouble booting up. Games with slightly stronger copy protection will not boot up he game, but will boot the warning of wrong console region. Such games include Comix Zone and Mazin Wars (Saga.)
The sounds aren't terrible, but there is a strange and strong distortion in some sound effects. As like the console would keep some channels down and some up while not being able to completely play them. The image is a bit lossy compared to the standard MD output, and loss is very notable when compared to the RGB cable image. However, it's really not that notable.
Controllers are good and might be our main reason to buy this machine. They're your standard faire and work well. The D-Pad is pretty damn nice, and the buttons are sturdy and can take a beating, and after some wearing down the buttons will become better.
It's a nice plus to get 20 games build-in, and for 20€ this was a very nice purchase to replace my long dead MegaDrive. However, this does not suit as full fledged replace for a mentioned reason. Buy it for the games and controllers it offers, and try to search for a genuine article and mod it.