Coming from and O.S. to a werks B5 and also a werks B7...
After learning how to tune the B5 and B7 which is easy. I have to say the B5 has low end for days and the B7 is a very smooth and powerful motor.
It really depends on your driving style. Like Tebo was asked why do you run the motors you run? They don't get good Fuel mileage. He said I like the way it runs and plus I am hard on the trigger. So Its really more of along the lines of what you want out of your motor.
I had GRP before the O.S. (V-Spec and Speed).
The Pipe you use really sets the point of how the motor will do. Throw that into the mix as well...
Just my two cents....