Sure, you return an iPad once, it can be arrributed to you being unlucky and shipped a faulty model. But anything more than twice, I am inclined to believe that the issue is more of the buyer being needlessly picky and having unrealistic expectations.
I went thru 5 New iPads. #6 finally has an acceptable screen with no major distracting blotchy discoloration (though the slightest change in viewing angle still yields a noticeable color shift). What's so unrealistic about that?
What's unrealistic to me is that both my iPad 1 and 2 were great out of the box, screen quality wise, but that myself and several others here have been thru multiple iPads trying to get one with a comparably evenly colored/lit screen, with more and more people are chiming in every day with the same complaints. And yet, miraculously, the "vast" majority of other iPads are deemed "perfect".
This either indicates that there are mysterious pockets of black clouds of bad luck that follow a select few around the world, from store to store, from batch to batch of iPads, or that the "vast" majority simply can not see the issues we see.
If you blow a dog whistle and only dogs can hear it, that does not mean you are not blowing a whistle.