You also got to remember where you are riding. I have a banshee (mods are below and its for sale!) and a 700. My 700 will kill the banshee on anything but sand. In sand, it's hard to say. My raptor was recently dyno'd at 51.5 HP with slicks and at sea level. All i have is a PCIII, exhaust and filter setup. That's pretty close to a banshee with pipes, filter and jetting if not more!
Personally, I love the banshee. However the longer I rode it, the more problems I had. I owned it for 6 years and had to rebuild it three times in the sand. Not to mention the numerous other nickel and dime fixes! I am really good with pre-maintenance however no matter how much I did, it was never enough!
Two of my friends bought brand new 660's and the only probs they had was tranny re-gearing and starter clutch. Thats pretty good for 6 years of ride time!
Bottom line, the banshee will always be the king of the dunes, but your pocket book better be deep because your gonna tap into it for parts! I'm 29 now and I no longer want to work on anything in the sand. When I drive 6+ hours to get there, working on the %ucking banshee was the last thing I wanted to do!
Banshee's are like an ex-girlfriend. I'll think about riding her all the time, but I'll be damned if I want the $itch back!