i currently have a slow DR250S & i want loads of power so 600 is the way to go right? but the extra weight has me considering a 400 - 450. im looking at DR's, XR's, that sort of thing, enduro bikes, so would a 450 be as powerful as a 600 because it is lighter in weight? im told 400s corner better too, would a 600 have that much more weight that its only slightly more powerful than a 450 or is the power loss minimal?