I'm running MAME ver. 110 on a P4, 3ghz, WinXP home with 2GB RAM ... it plays everything I throw at it (well, except for Radiant Silvergun

). The only slowdown/glitches I experience are those games that haven't been emulated correctly yet (see previous parentheses)
As such, I'm of the "if it's not broken, don't fix it" belief. That and I cant be bothered tracking down another full romset, since I already got one for ver. 110 (4o gigs worth .. sheesh!)