I plan to buy a new iMac 27" 2.8GHz Quad i7. My question is in calibrating the monitor. I have read that on the 24" monitors(or 21? one of them) there is a brightness problem & some of the calibrators can't function because the monitor is too bright therefore requiring "Shades" or "Coloreyes Display Pro" to enable the calibrators to work. Is this a problem for the 27" monitor? Which calibrator will inclusively do the job on this monitor(without buying additional software to enable it), Colormunki?, Spyder3?