I'm guessing that as you don't get a product code until you run the install on a machine you're upgrading, that's all the check they need, and future reinstalls won't be an issue.
I have my backup DVDs now - 32 and 64 bit in a cardboard sleeve, but no code stickers.
I have my backup DVDs now - 32 and 64 bit in a cardboard sleeve, but no code stickers.
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