FedEx will deliver my new 2013 13" MBA on Christmas Eve, to replace my 2012 11" MBA. (I upgraded primarily because I needed more screen real estate.) I have a cheap clear plastic hard case (I think made by Speck) for my 11" which, frankly, is a piece of junk. It constantly slides and pops off the laptop. The vents in the bottom piece have caused some sort of weird discoloration on the computer's finish and have allowed multiple nicks and scratches to deface the aluminum finish. The best part about the Speck case was that it did not significantly alter the size or appearance of the computer, but overall it's been a huge disappointment. So, for my new 13", I want to do things right. I need a good case or sleeve that will withstand my moderate-to-rough use. It also needs to work well with my briefcase, which is a Filson Padded computer bag, which can accommodate a 15" laptop, I think. I'm willing to spend up to $75. Thanks.