I had two 150gb 10k raptors. Hated them. Noisy as hell and in my quiet office it was irritating. I went to two Hitachi 750gbs in a Raid 0 and found that encoding movies wasn’t that much slower. The raptors saved maybe 3 seconds per minute of movie encoding. Since I don’t do clips more than 30 minutes at a time, the extra minute was worth it to cut out blue-man group performing Mandelgroove in the case.
I have the same complaint about the noise, it’s really excessive in my 150GB RaptorX drive. I’m still using it though for the OS, but I put in a RAID that holds all other information to try to minimize the horrible speed up speed down clicking noise from the RaptorX.