FLAC > AAC, unless it is the Lossless AAC you are talking about. The fact that Apple does have a lossless codec but doesn't offer it on i-tunes is reprehensible to me.
I will never understand the kids of today "Settling" for a bunch of code on their i-pod that if something happens to it or your Computer HD you will have to repurchase all the songs you lost, unless you burned a transcoded CD, which I have only done twice before I gave up on them.
CD's you can do whatever you want with them after you rip a backup on your PC, AAC, MP3, ACC, Ogg or whatever else you want, and if something happens to your portable or HD you still have the originals at home.
Does anyone really need any other reason to hate i-tunes and what they stand for?