that's right you can't compare an IPS panel to an TN panel. iMac have a rather bad IPS panel though people tend to think it's amazing due to its over brightness and over glossiness...It looks nice maybe but in fact when it comes to color reproduction it is not just as good. But I see how you feel any IPS panel looks million times better then a TN panel. Imagine difference between my color calibrated DELL Ultrasharp and G75's TN. Miles and miles away...but I have no trouble looking at my external screen wile the G beast is under my fingertips.
ASUS G75VX
Win 8, i7-3630QM, 2,4 GHz, GeForce GTX 670MX, 8 GB Ram,120 Gb Samsung 840 SSD+750 Gb HDD