I care about mame greatly, even though for SFIII/3rdStrk I need CPS3. The only emu I've used more is WUAE!
But although my CPU is 64 bit I'm still running 32 bit Windon't. (I'll probably only update my OS when WUAE goes 64 bit, if there is indeed any advantage in doing so...)
Back to mame, yeah, I just "upgraded" to mameUI and then quickly went back to mame32 cos of compat problems (a full three-fourths of my shit wouldn't even list).
EDIT: btw, I like the Strider image in the top left, Ian. ;-)