I have heard that some 4 way games act bizarrely when you hit the diagonals, like walking backwards or sideways. I don't know which games this is an issue for, but you may want to set input in MAME to disable the diagonal directions.
I have 2 Happ competitions in my cab in the are mostly fine for Pac man, Donkey Kong, etc. Just takes a little getting used to. I started out playing on Happ sticks though, and if you grew up playing on 4 way ball tops I can understand how it's just wrong to use anything else.
And I second the sentiment that whatever is fine for you in YOUR cab, is fine for your friends.