abit built a fantastic reputation for overclocking when they released the bh6 (i still have one). so yes it (kt7a) is the ducks guts for overclocking, but only for the experienced (so many options)
as for will it run 1333? i cant say yes for sure as i dont have one, but i would bet my left gonad that it would be a dream combo
currently i run my AXHA T1000(100x10) at 1133(133x8.5)
on a k7ta (not raid)
interestingly enough, AMD site no longer recommends kt7a, one reason i have pondered is the lack lusture performance 'out of the box', to be honest , i was afraid i'd made a mistake (amd,via,abit), but now after much tinkering (and learning!) this thing blows chunks (good)
ps try and get the AXIA or AVIA steppings that every one rants about.