Just to let you know, you can burn Lion to a DVD after you download it fro the App Store. You can then use that anytime you want to reinstall Lion. Disc media is starting to be phased out bit by bit.
The DVD divers in my computers get used 2 times a year at most.
Also, the Air acually pretty *censored* fast thanks to the Solid state memory, and how OS X manages it's self. Macs aren't cheap, but they are by no means terrible. Also, the Air isn't a nethook, so I don't know where you get the idea that should be compared to one.