I have a V. Raptor and while it does perform well on a SATA II set up, I think you'll see the best results by going with the Caviar Black, i.e. more storage and a bit better performance, especially on a SATA 6 set up. FYI, both links are for the Caviar Black.
If you are interested in performance, as indicated in your original post, then the Velociraptor is the winner. Not necessarily by a wide margin, but it will win most benchmarks. Is it worth the price premium to you?