Looks fine from the nostalgic point of view, only 4 games are few, but believe me, that micro things/consoles are playable and in real the screen looks better. Funny stuff.
Sure that the Micro Game Gear are bigger than the Keychain/console that i got ago a year hahaha... and is very playable and high quality stuff! But very very little. I say it again, looks better the screen in real than in picture. Another issue is if your fingers are a bit fat... but keep a worth:
I like the idea but there's a couple things that put me off. First of all, the dimensions of it would make the thing smaller than a Gameboy Micro, a single Switch Joy Con, or a credit card. I can't imagine this being very comfortable to play with.
Secondly, I don't like having to buy 4 of them to get all the games, because that means you're paying $200 for 16 games. Compared to the Genesis mini which was $80 for 40 games, it just feels like a rip off.