Here's a recent article by Kevin Cameron on what the technical differences are between the two engines and why.
II had read it and was going to post it here too. Very good read. Makes me think about what.a good set of cams might do in the even degreeing can't get to where I'd want to be.
Overall I am pretty happy with the power the bike for how I use it most. But since I am greedy, I wouldn't mind a bit more. Don't need SDR level of power since the bike is lighter but another 10-15 HP would be awesome.