I joke about the big/small differences. I am lead to believe there is no substantial 'seat of the pants' difference. The 790 has the edge on HP. The 865 has the edge on torque. I would be inclined to thing that the solo rider with a zest for zipping at a healthy rate would best enjoy the HP, while the high gear lugger, the 2-up rider, and those riding with a lot of gear would appriciate the added torque. I have nothing bad to say for the 790 and there are those that can attest I'm far from light weight. If you can get a good buy on a used 03 from someone reputable, I don't think you'll err. Conversely, if the 865 is your chosing, I don't think you'd be sorry either.
