Get a 4mil Serval and you should eat him for breakfast, lunch, and dinner. I had a yfz450 that was pretty built...44mm Lectron carb,big bore, cams, pipe, intake..(packard racing set the motor up). That alone I was giving some ported banshee's a run for their money. But....I ended up selling that for my 06SE banshee and I couldn't be happier.
Just remember, the guys with the super fast 4pokes have to put double the money into the motor than you will have to on your banshee.
-Zach