Acutally there typically isn't much debate

Happs horizontal pushbuttons with microswitch!
They have a concave feel to them and are generally the preferred pushbutton..
There have been a few messages regarding convex vs. concave... *some* people prefer the ultimate pushbuttons for fighter games because they can mash the buttons faster

Do not get the vertical pushbuttons as they tend not to be as durable (so that i've heard)
You can get the happ horiz PB for 1.40 each from Bob Roberts.. (comes in 8 diff colors I believe)