Others say...

"Buggy Software"
I have a Spyder2 Pro at home, and decided to get a Spyder3Elite for work. Mistake. The new software for the S3E is buggy and the UI is awful -- it's like they forgot everything they did right with the S2. There are many bugs, especially if you try to calibrate more than a single monitor -- half the time (or more), the calibration software gets the monitors confused. It will put the calibration patches up on one monitor, then when you get finished and select "Switch" to see before and after color LUTs, it switches color maps on the wrong monitor!

The UI is a catalog of what not to do with modal and modeless interfaces. Cancel in expert "Measure" doesn't take you back to the expert screen -- it takes you to some other random screen in the wizard sequence.

The close box is often not active -- instead you have to use File->Quit (and ColorVision's insulting tech support says they did this deliberately).

The list goes on and on, but The Big One: poor calibration! I ran both wizard mode and expert mode, then used the colorimeter to check the color temperature of gray patches, and the S3 calibrated colors were all over the map -- different by thousands of degrees. The S2Pro calibrated results were nearly spot on from near black to full white.

The S3 calibration software is in need of a complete re-write, at least from the UI perspective. This may be the best calibration hardware, but I can't tell since the software that drives it is so bad.

Maybe it works on Macs -- can't say -- don't use them. But on Windows, with an NVidia 8800 GTX, the Spyder2Pro is a much better bet, at least for now.

"ColorVision support is miserable."
I have been dealing with ColorVision support for over a month now. I don't feel that Spyder3 or Printfix has been able to perform accurate results. Anytime you call their 800 support number you wait on hold for 20 minutes just to have some guy write an email to someone about your problem and tell you to wait for a response. When the response finally comes it is canned and doesn't actually answer your questions. I sent my equipment back under their 30 day money back period and have been waiting for 3 weeks for my refund. I wouldn't buy anything from ColorVision ever again. They need to learn how to support their customers and handle problems without a 24 hour waiting period for a canned response.

"Great so far"
I received this only a few days ago but so far I really like it. I previously used the Huey and Spyder2pro and think this is worth the upgrade for professionals. The ambient light sensor is a good bonus compared to the previous version and the reduced size of the product is much easier to transport in a laptop case though nowhere near the huey in terms of portability.

Thus far I have only one critique but I hope it won't matter. The cable is a fair amount thinner than the Spyder2 and the counterweight is kinda tight so you have to be very careful not to damage the cable when moving the weight. It does come with a suction cup that is removable but I don't use it, preferring to use the counterweight since I don't care to clean suction cup marks off the screen (matter of choice.)

All in all I think this is a great upgrade to the Spyder2 though not an absolute necessary upgrade for people happy with the Spyder2. It is faster and more accurate (to my eyes anyway) and other than the somewhat thin cable, it seems well constructed.

I don't have an enormous history using calibrators so take these words with a grain of salt.