Ah, I see. I would think they would look more into the history of a laptop then iPhone 3G, but I have no idea. I'd love for someone who knows to comment.
iPhone 3G is like a disposable electronic, the way it's manufactured and replaced all together.
I'm willing to bet that the answer is no. Not that they couldn't probably find out if they wanted but I don't think that it comes up automatically. I'm in the double digits of replacements and not once has a Genius ever mentioned the other exchanges.