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I love the unibody. I've watched the video of how apple machines the unibody from a solid block of aluminum. WOW. I have two, one from Nov 2010 and one just bought. I admire these laptops almost as if they were works of art.

So, when I got ready to sell one of them, and cleaned some dirt off with a moist cloth and a bit of soap, I was not looking forward to discovering that there's is a dirtly little secret I didn't know about:

Unibodys have some sort of coating, and that coating came off with a bit of moisture and soap. It changed the finish and created opaque, matte, whitish stains on parts of my unibody - just like when you rub paint off a plastic product.

If it ever happened to you, you will know what I'm talking about.

I'm taking it to the apple store tomorrow, see what they have to say.
Who'd uh thunk it? I have owned three MacBooks Pros in the past three years. I wipe them down with clorox cleaning wipes. I have never had this problem or any like it.
 
Glad it worked out; I use the magic eraser maybe once/year just to clean up stubborn stains.

As others have mentioned, it is practically speaking a really super fine sandpaper sponge, so I would not use it too often or scrub too vigorously.
 
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