Listen to this advice,I have an '07 750. One of the best things about gsxrs is they're easier to work on. And many of the same tools/parts are used with the busa and the gsxrs. For example, my 750's oil filter is the same as my busa's.
If you don't work on your own bike, then I would go with comfort first.
I say GSXR all the way, and make some adjustments for your size.