there are a few known bugs, you can find about them by searching google
i'm guessing home premium might be the harder one to find on shelves at first, but i dont think they have the same type of manufacturing problems like you do with consoles, i mean its a dvd and a box/w manual..so i imagine they should be plentyful
however staples.com/vista has free shipping and a free 1gb usb flashdrive thats vista certifified for readyboost so i did that route and got ultimate edition so with taxes it was like $423 and 1 day delievery