I have a Raptor and it improved my build times considerably. I say go for a Raptor. The i-RAM is pretty cool from a geeky perspective but the reality is that I'd rather just add more ram and make a ram disk on my own. That's my two cents.

Oh, and the VelociRaptor just hit Newegg's site.

Well I decided on an i-RAM. It came yesterday and I finally got around to setting it up today. Visual Studio 2008, ReSharper, MySQL, and my project files are all on it. The performance boost wasn't as great as I hoped, but it is still a lot better - takes probably half the time to both load and compile. So, was it worth it? I think it was. It was a total of about $275, which is quite a bit for such a tiny thing (4 GB), but if you have some smaller I/O intensive programs you want to speed up, you might want to consider this. Though it'd be best to wait until someone comes out with one that can actually support DDR2 RAM and 300MB/s SATA. ;)

Thanks again for your input, everyone.