The Mega Drive Mini 2 is an amazing mini console. It includes 60 games (53 original plus 7 "bonus" games) that represent some of the best in the Mega Drive/Genesis/Sega Mega CD catalog.
There is also great variety, meaning there is bound to be a game for almost everyone.
Used it with the "officially licensed" Retro-Bit Genesis wireless controller (2.4Ghz) and it worked great.
I have both original MegaDrive consoles from the 90's including the Mega-CD, so I can say the emulation on the Mini 2 is good no slow down or any bad latency with sound. The only downside its expensive for what it is considering you can do the same thing on your PC for free i.e. emulation and ROMS. Also, a bit of a missed opportunity with a lot of IP's that could have been on the mini 2 console.