I don't know what the 2002 ZX-12Rs are like. They were supposed to have tuned them for mid-range performance this year. I'm sure they are all still running somewhere in the mid-9s with experienced racers as the previous years (although, remember that MC rags will always give largely biased numbers, favoring one over another... that's what they're paid to do).
As far as the top end goes. I have no clue as to whether the newest ZX12 is still capable of speeds near 200 when unrestricted. I have only heard a little bit about the 12's reliability. The busa has proven to me its reliability, with the daily abuse I put mine through it is still as strong and hardy as new (almost like Timex
).
I wish I could tell you more, but I have never owned or worked on and ridden a 12. Although I had the opportunity to have both a while back, but finances shot a hole through that dream.
I have a video that compares the two, in depth, back in 2000. Basically, it comes down to which color you like best. Both are very capable bikes. Your best bet is to cruise some 12R forums like zx-12r.org Offline and judge for yourself based on what you specifically want. Look at things like recalls, common problems, complaints, mods and such just like you see here and on . It's always hard asking these questions on brand specific boards.