I have a late 2008 MBA running snow leopard. I would like to have this system reloaded from scratch with mavericks. No upgrades, no loading one OS and then loading a newer one on top ... I am going to boot to a linux CD and dd my hard drive, wiping it out completely. Then I will go to genius bar and just shrug and say "me want mavericks". Two questions: 1. Am I correct that they can just boot off USB mavericks install media and load mavericks from scratch, with no upgrading from one OS to another ? 2. Any reason this won't work or will backfire or ... something ? Thanks.