1) Out of the SATA compatible drives available, I'd say the WD74 is the highest performing overall, however the Maxtor DMAX10/MaxLineIII with 16MB cache are supposed to be almost as fast (and faster in certain benches), although only 7200. But you do get 300GB (for roughly the same price iirc). WD74s are good, however they are old technology too, so they aren't as good as people seem to think.
Here's an interesting review including various top-perfomers
http://techreport.com/reviews/2005q2...6/index.x?pg=3
WD74 is best overall, although it doesn't win it all, and the competition is very close. Much closer than it could have been, had WD released anything useful till now. However, it might change. I've heard rumors of november.
2) Four 80GB hitachis (i e double the total space of two raptors) cost less than two raptors. In Sweden you get 6.5x80GB Hitachi SATA II for the price of two WD74 raptors.
Fool! :D
That's one out of many SATA-IO requirements, yes. Your point was?
Some more links if you're interested
http://www.sata-io.org/namingguidelines.asp
http://www.sata-io.org/faqs.asp
or simply read about what you wish:
http://www.sata-io.org/