sunruh,
The Vstrom is shifting about the same as when I tried Rotella T 15W40 about 17,000 miles ago. It is a little notchy, but has been since new with Rotella Dino or SuperTech Dino when oil is new or ready to be changed. Have been running SuperTech 15W40 about 14,000 miles in the Vstrom.
My 07 KLR650 and 08 CRF230L both shift good with SuperTech 15W40.
Will probably be ready for a oil/filter change & UOA on the Vstrom in June. Will post results, good or bad for everyone to see how this oil performs in a water cooled 650CC V twin mostly on mountain twistys operated at a moderate to spirited pace.