I have 5GB of space left on my RAID array. - For $450 I can pick up 3x 150GB VelociRaptors and get 2x my current storage capacity. - For $180 I can pick up 3x 250GB WD RE3's and get 3.3x the capacity, but I'll take a hit from the increased latency. - For $140 I can pick up 2x 320GB WD RE3's and get 2.1x the capacity, but I'll take two hits from the increased latency and from lower throughput. I'll also have an empty hot-swap bay, which doesn't really matter, but I feel like I should be using it since I have it. I was really happy with the Raptors back when I got them, but I was stupid and I didn't provide them with any cooling at all, so now when I run a disk check I can hear the heads bouncing all over the place reading substitute sectors because a bunch of the primary sectors near the beginning of the disk have gone bad. That is eating into my bootup times something terrible. I don't really know how much "normal" hard drives have improved since I got the Raptors; the access times are pretty much set in stone, since the speed of the platters hasn't changed any, but maybe that doesn't tell the whole story. One thing that could mitigate the decreased speeds from the slower drives is that I have an IDE FLASH card being used to cache frequently-accessed files, and during a bootup simulation it shows the cache-assisted transfer speed is ~4x faster than with the hard drives working alone. But...cache-assisted transfers with fast drives is even better than cache-assisted transfers with regular drives. I don't want to spend money on this computer at this point, but I can't bring myself to replace it either. I've got it set up just the way I want, and it does everything I need. Replacing the hard drives should kick it back up a notch, because it will actually boot up quickly again, so that would be nice, and I've got cooling on the RAID array now so it won't go bad again. What do you think? Go balls-out and get the best hard drives on the market, or just go one-ball-out and get decent hard drives that will do the job without the bling factor? Even $450 is better than $2000 to build a whole new computer.