After much deliberation I've decided a MBA 13 is right for my needs, but I haven't found any definitive information on if the hard drive is enough. For the $300 in savings, I would rather get the 128GB model and a 1TB external, however I'm not sure if I've have enough room for all the programs I want installed: I take it the HD starts with ~121GB, minus ~10GB for Lion. Leaving me roughly 110GB for iTunes, iLife, Office 11, Adobe CS 5.5, Draftsight and maybe the odd game like Starcraft 2/ Warcraft 3. I would like to leave a 20-50GB buffer for working files. Will this be enoughr room, or should I spring for the 256? Caveat I also have a gaming PC from 2009 but want to leave it to be mostly a media rig.