I have a 13 inch and I have had no problems with mine at all. It's very fast, has great battery life (sometimes I go without charging mine at all for 2 1/2 days) and it is very lightweight even though it is the larger screen size out of the ones available.
There's great apps available from the App Store that I find helpful with learning. Evernote, Grafio and the standard Pages, Keynote etc. I do have Office installed too, and it's nice to be able to choose between the two.
I do recommend getting extended warranty and a larger hard drive, as I've had mine for not even a year and I've already used up a fair bit of space. Keep an eye out for ex-demo models too, as they can be quite a bit cheaper but essentially the same as a new laptop. I got mine as a ex-demo from JB because someone bought it thinking it was a Pro and the guy took off $400 from the RRP and gave me a free case and 3 year warranty. Shop around and get the best price

Now that the Pros don't have CD drives in them, I couldn't really justify spending more because I wasn't doing any heavy footage editing. If you're mainly using it for word processing, photo storage, internet etc, I think the Air should suffice quite well