I ran a quick spreadsheet of MPH vs RPM for the different TKO-600 setups, with the rear ratio in the top left corner and the gear ratios down the left. What do you think of the 3.31 rear with the 0.82OD? My motor should be in the high 500s for hp at the crank, with torque to match. I'll have to figure out my cruising RPM in the next few days.
EDIT - By the way, this is calculated with 26.5 inch diameter tires.