I tried the tighter belt and it might have been a touch better, but it's so tight it won't idle, so I went back to the previous one. Worked the bike out hard today on the few little trails we have and plenty of full throttle 200 yard sprints. When the kids got home, we fired up the 200EX and had a big time in the field with 25+ races. Obviously, I was able to beat the throttle limited 200EX every time, so we worked out the lead time needed for a close finish. Interestingly enough, they both came off the line about the same, although the EX was hauling 100+lbs less. The TAV equipped Baja didn't really pull ahead until the EX topped out. Never smoked the belt despite all the hard launches, it actually seemed to hook up better as time went by, not sure if wore in, or just got sticky from the heat!
Couldn't help myself ordering a 7 inch driven pulley and belt, just to see what it was like. I'd still like some rooster tails!