I have a 2009 R3T, and a 2007 'Busa. Both are showroom stock.
The 'Busa seems MUCH faster to me. No contest. But that's obviously based strictly on my very own butt-o-meter, and nothing scientific. The R3T does very, very well up to about 90, but the 'Busa just keeps on accelerating - until I run out of road, or out of nerve. It's as smoothe as silk, at whatever speed you care to ride.
However, if you gave me 3 hours to get from Knoxville to Atlanta by bike, I'd take the R3T, though. No question.
CW