My 17" MBP has also had a problem, back to the chappie at Hemel Hempsted for repair, £500 of parts, all fixed. Er, no, actually: the new part has also failed, back off for another visit to the doc
But it is a good reminder to pay for AppleCare
Re the MB Air, I use mine all the time these days, it's just the best bit of kit for travelling. But it doesn't have the grunt of the Pro, although at less than half the weight that's to be expected