We’ve been in the same boat with the 724. We actually returned ours and purchased an Eizo CG241W in its place. While the colour gamut isn’t as large as the 724 we can calibrate it reliably and the colours are accurate.
That said, we were experiencing colour issues with the Eizo when we first put it in. Colours in PS were over the top, particularly in the reds. After a great deal of testing and trial and error we discovered that when the OPEN GL for the graphics card is activated in Photoshop (Preferences) it can throw your colours off dramatically in dual display environments. We turned it off and all is well. The downside is we’ve lost some functionality in PS with GL turned off.
As a follow up we also re-tested the 724 at our shop with Lacie support on-hand. Still no success as of Dec 16, 2009. It calibrates perfectly on it’s own however in a dual display environment we just can’t seem to make it work. It’s a shame given the benefits of a full Adobe 98 gamut.
C.
RE. calibration device… the i1 Pro works perfectly for calibrating the 724.