Colorimeter help

[Fading Phoenix]

I'm about to hit the bunk, but wanted to throw this out on the big wide web before I do.

I've put this off for a long time, but I'm considering getting a colorimeter. I don't really know much about them though. I'm hoping I can get some advice and lots of opinions.

The girlfriend and I both do work in photoshop and lightroom so I would like to get one to use on both computers (I don't know if some may register to the computer it's used on or not, and don't want to end up with only one calibrated display)

I'm currently on Windows 8 and she's currently on Windows 7

Her monitor is a Samsung SyncMaster 215TW

Mine is a Dell 2709wfp so the colorimeter will NEED to work with a wide gamut display. This is the part I've been most concerned about.

I'm hoping under $200(?) for a tool I'd be able to reuse for both our machines consistently. Obviously though, the cheaper the better

Thanks in advance.