I'll strongly recommend against the use of a Velociraptor (Or any 10000 RPM disk) drive (The heat generated is really great, the ventilation in the PS2's disk drive bay isn't good, and 10000 RPM disks generally don't last as long as any slower disks).
Originally Posted by Clement
The PS2's DVD drive isn't very fast, so you don't need a really fast disk to even beat it (5400 RPM disks will do, but they're quickly disappearing from this world).
SSDs are OK, but they're expensive.
OT: That adaptor looks nice. I wish that I can get one.... but I can't because I don't own a credit card yet.
SCPH-10000 S. MINOKAMO v1.01 (Defunct)
SCPH-10000 S. KISARAZU v1.00 (faulty)
SCPH-15000 S. KOHDA (With warranty seal!) :D
DESR-5100 S. EMCS