Using a MBAir 5,2
Someone was bugging me on why I would bother, and first, because I could and secondly, I am getting the actual 7-8 hours rather than 3-4 using OSX from charge to charge. It has an SSD anyway so i don't know what OSX does that is eating so much battery. Even with nothing other than a browser running, the battery gets sucked dry in half the advertised time.
The latter, I just followed the power management tips and the lightnum tip. The rest works with 12.04.3 pretty well.
and I am using actually a class 10 micro sd card in