Not the one I sat on . . not much difference although they say it is lower. I sat on both on the showroom floor and there couldnt have been more than an inch difference at most.
I'm 5' 10" and my knees were bent and feet flat on the ground on the T-Bird. I have a Corbin seat on the R3 which is pretty wide. That could make it feel higher. However, I thought that U-turning in a tight space was a lot easier than on the Rocket. Maybe that's because of the wider bars. I have Ultra Classic pullbacks.