I'm going to buy a new Mac tomorrow... upgrading from a 2008 uMB. I'm looking at the base model rMBP (8gb, 256gb SSD). I have a 500GB in my Mac right now. While I believe 256GB is plenty of space, I did have an 80gb Windows partition. Would it be possible to use an SD card to boot Windows 7 from? There are 64gb cards on the market which would be plenty for me. Thanks!