OMFGz0rz! You're NUTZ! NOEGEO IS T3H BEZTTZ0RZ!!
Naw really I do love the Neo, but I have to agree that for arcades (specifically) they were a bad idea. The machines were slightly expensive, but while it could have 1 to 6 UBER awesome games like Pulstar, King of Fighters 98, etc... Only two people could play ONE game at a time, so other arcade-goers would have to wait to play their desired game.
But if we're talking 'for the home arcade' usage, oh man.. Neo 6 Slot cabs are tha shiznit. You really don't need anything more than a 4 slot, but still, they are awesome 'have in the home' cabs.