Should I be worried? I mean this is my 4th one. (27" i7) So, iMac #3 went back to the Apple Store. Dead pixels ruined an otherwise perfect machine. No gray band at the bottom, no yellowing, quiet, really nice. Except a dead cluster of pixels on the upper right of my screen. I had to return it for iMac #4. Really did not want to. So, here I am at iMac #4, and the yellowing is not an issue, it is quiet (even with a Seagate drive), a miracle - I know. However, with iMac #4 I have a significant amount of gray banding on the bottom of the screen. So much so, that I might have to re return it. I even started this one up in the Apple Store. I pointed out the gray banding to the sales guy, and he called over a supposed "Genius". The Genius when on to say that they all have that, and that it was normal. He went on to say that "We cannot keep exchanging these things", even though this is only iMac #2 at this store. Backing up a bit, my 1st iMac had a cracked LCD, bad gray banding and bad yellow tine. My 2nd iMac had a bad DVD drive and yellow tint issues. I called Apple Care (it was a BTO) and explained my issue. The Apple Care Rep said "Apple's policy on the new iMacs is that a yellowing tint is considered normal." and he would not guarantee that I would get one without it. I was told that I had two options. 1st, was to get a new display installed. He then told me that Apple was only allowing ONE display exchange for the yellowing issue. Even if the new display was worse. The second option offered (which I took) was to return it for a full refund. Now back to why I should be worried. I am looking at iMac #4 and the gray banding on the bottom is pretty bad, but the store does not want to do another exchange. What do I do? Take it back, and then go to another Apple Store and start over? Should I be worried that I will never be happy? Darn iMac #3 was perfect in every way, except dead freaking pixels. Am I just unlucky? What a royal PITA this is.