well zen garden isn't a game... but will just say it is and yeah some games run slow or leggy on iPhone 5. I still using it for now because I don't want my iPhone 6+ to be smudge yet. haven't got a case or protector yet
I'm thinking of getting a 6+ and jailbreaking my 5 and turning it into a gaming only device. Just a thought.
The black front panel looks really nice and glossy and it looks like a bigger screen because the screen and bezels camouflage and the plastic lines on the space gray blends more. But if you don't care about that you can get silver or gold whatever is best for you.
The iPhone 4S with ios8 is very slow. But I'm still on iOS 7 and the speeds great. Love my iPhone 4S as it's jailbroken, runs quickly and you can pick them up cheap So far I think there's only 2 games I would want which I can't play (the wild and bioshock). Vast vast majority run fine on the 4s
