I have kind of an old air, 10.5.8 on it. A friend of mine that had 10.5.x lower than 8, had trouble jumping straight from 10.5 to lion. I am wondering would I have the same problems or would is be straight forward for me? Also it is a mac book air so no cdrom and it doesn't have appstore so I have no idea how I am going to even do this without a usb book hack. Any pointers?