I like the dual personality of my bike. 2500-4500 she is almost like she was stock, powerful but smooth and predictable. That's really a plus riding 2 up.
Above 5000 the power comes on like she's trying to throw me off the back.
I really realized the purpose of the bipolar attitude when riding 2 up with friends. We were rolling along about 70 mph when the front bike signaled for me to take the lead since I was more familiar with the area. I dropped it to 3rd and rolled on it a little hard. It started picking up speed, then the front tire lifted as it started hitting the power band. I couldn't imagine having a passenger with that much torque and hp down low. I'd have to be way too careful with the throttle, even at walking speeds.
Plus with all of the fun power at the higher rpms, I can cruise at 3000-3500 and get 37.5 mpg. Seems like a win win to me.