Good choice Boneprone - whats the monthly rub on that? I was hoping you wouldn't do server A because it was pretty much a lateral move... and server B wasn't all that either - server C was the right option the whole time, the only way to have bettered that would have been to go with SAS drives.
With regard to the comment earlier that the Western Digital Raptors are consumer drives thats not true at all. They are enterprise quality and come with a 5 year warranty. The only reason companies like Dell don't put Raptors in servers, or at least even low or mid grade servers, is because they like to sell more expensive drives. Additionally, they never came up with a compelling offering of larger sizes... like the 300gb and now 500gb SAS drives. If you read performance reviews on
http://www.tomshardware.com it's an excellent reference for processor comparisons and HDD benchmark performance. To answer the other earlier question, all Raptors are Sata 150 none are 300.
Also, a side note, the 15k drives aren't all that they seem at face value. Manufacturers like to let you just simply assume that they up the performance ante by 50% when that's not at all the case. They typically benchmark out only slightly faster than the 10k sisters... and depending on the application, manufacturer model, you're going to see really varied results.
Brad