rkk01.
You don’t say whether you’re using an APS-C or full frame body. If you’ll forgive the assumption, I’ll go with APS-C reviews.
This review sums it up pretty well, and it’s of the Sigma AF 70-200mm EX DG HSM APO, Mk2.
By the same guy, here’s a review of the Nikon mount, Mk3 (Macro) issue of this lens.
I have to agree with Klaus at Photozone.de. I find him pretty objective. My lens was around £700 new, in 2006.
Yes, the latest version at around £930 has Optical Stabilization.
Much of your success at the IoM TT races will depend on your technique.
I’m no sports photographer but the first time I tried birds-in-flight with my Sigma 70-200 the results were shocking!