So I have a stuck/dead pixel on my iPad 2 (for the second time, first one I bought had a dead pixel, returned it and this one does too)

I purchased it as Best Buy, the first one I returned was black and was able to be seen on the grey background that shows up after you restore the iPad to factory settings. This one is blue and can only be seen on a black background. The first one I had to prove to the guys there that there actually was a dead pixel before they'd swap it out. I'm worried about this one because, as I said, you can only see it on a black screen and I'm not sure how to get a black background to show them when the iPad is in it's original factory settings.

How should I approach this return?