Two words - bad ass.
I don't think there were any cars with more power than I was running out there including the 17.5 guys. As usual, the driver was a bit suspect, but I did hang on to finish in 4th which wasn't too shabby for a guy that hasn't pulled the trigger since November sometime!
FDR on rubber tire was 6.5 for me using the 4499's (which I ran with in the main). I found dropping a tooth when I was running F-brushes kept things about the same. The 4499 makes notably more torque, and the F is good for another 1K RPM or so.
Great top end, and very strong out of the corners. Seemed like I could reel in most cars much faster than I was used to in stock.