Hey Blast,
I just passed 10,000 miles on my original BT020 that came with my 05 Sprint and pretty close to the wear bars. I am 6'3" and weigh in at 210-220 (depending on how much beer the night before). I have been very happy with the tires and I absolutely love the bike; the heat from the engine was nice in January

I haven't been to track nor do I do burn outs but I do like carving the curves through NH and commuting to MA. How is the road surface out there?
Anyway, I also noticed that the tires are a little dicey now that they are worn, but I guess that would happen with most. After talking to many other riders I am going to purchase the Z6's, they are the same as the Diablo Strada but have a deeper thread pattern (8mm vs. 6mm) which "should" translate to more road miles.
From what I've read and heard from other users; the Z6's warm up fast, have excellent dry grip and superb wet grip. It has been noted to use the front and rear as a set; the rear tire has no center groove because the front tires moves the water on wet surfaces.
Well, good luck with your purchase and ride on.
Peace.