To those of you getting 8, 10, 12, 15 iPads and are still not happy: give it up. Return your iPad. You'll never find one you like and I can't believe Apple has been patient enough with you to even let you do that.
To those of you who think Apple is capable of producing a perfect LCD all the time: you need a reality check. LCDs are LCDs. They are made by the same companies that make them for all other devices. They are equally susceptible to dead pixels just like any other LCD. Just because there's an Apple stamp on the back of the device does not mean that the LCD was made by magical elves.
Are dead/stuck pixels annoying? Yes. But that's the beauty of the retina display--if you get a dead pixel that's not in an obvious location, you'll probably barely ever notice it if at all. I'm not saying you don't have the right to return it and get one with no dead pixels. I'm just saying when you finally do find that "perfect" iPad, it could still get dead pixels down the road. It's a freakin' LCD. It happens. And you'll probably just find other stuff that bugs you on every return.
My new iPad has one dead pixel at the top right corner. I can only see it with my contacts out, as my up close vision is way better that way. With my contacts in, I can't even find the thing. In fact, I haven't seen it since the day I first saw it, so it's either corrected itself, or it's just not obvious at normal viewing distance. My iPad 2 had a stuck blue pixel. That was way more annoying as the pixels were larger, but still it never really came into my field of vision unless I loaded up Wired Magazine--the first screen is neon orange, and then I could always see that stuck pixel.
Weigh your options before doing these ridiculous amounts of exchanges. Is it worth torturing yourself over and over and spending time and gas money going back and forth to Apple stores? Nothing, not even an Apple gadget, is perfect. They have terrific design sense, and make amazing gadgets, but that doesn't mean they're perfect. I have done my fair share of exchanges (I had a lot of dust under the screen issues with my iPad 2) and Apple has almost always been really cool to me about it (except for one time when I got a really snotty kid helping me). But at some point enough is enough.
Some of you guys have to realize how ridiculous it looks when you've done this number of exchanges, still aren't happy, and then keep coming back to the forums to complain about it. The definition of insanity is "doing the same thing over and over and expecting a different result". If you're unhappy, return your iPad and get something else. End of story.