I have purchased some risers for my SV, as suggested from other replies. I hope that we are both happy by the time we get to test this suggestion out.
Sit on both (if possible) and choose the one that fits you best. Probably not enough difference between the two to really matter for track use. Both should have slipper clutches as standard equipment. I've always been a Kawi fan, but Yami's are good bikes too, and the R3's, 6's, and 1's are super popular too, so they must not be too bad either. To me it would come down to a matter of which one was in the best shape, a better ergonomic fit, and at the cheapest price. Good luck!