24" imac montior calibration

For those of you who have successfully calibrated your new 24" alum iMac, which calibration hardware / software did you use? I've seen spyder 2 mentioned, i1 mentioned and one other whose name escapes me. All are $300 or less, so that's not an issue for me.

By successful, I mean the monitor displays accurate colors (within tolerable limits), and your prints match your screen (again, within tolerable limits).

Thanks in advance.

Larry