whenvever I go to FS/Best buy I always go check out the iMacs they have on display to see what problems they have...they ALL have dead pixels, humming sounds, etc. Prove me wrong, but I have never actually seen a 24" iMac that is FLAWLESS.
For some reason I can't think of what FS stands for but have you tried an Apple store? All of those display models get abused but just like everyone else everytime I go to the Apple store I walk around the perimeter playing with the Macs and I can only remember being consistently in awe. I have stared at the 24" iMac screen countless times, beautiful if you ask me.