The best i don't know.
But Atomic can do that. It has a coktail mode. And lot of users use it in a coktail cab.
But i'm not sure that NEO GEO games have a coktail mode?
(i mean that the screen flip when the player changes)
Anyway, a guy from here did a interresting modification on MAME which allows to play games where player plays simultanualy on a coktail. So using that, it could be good.