I find the Alac files are a little bit smaller than Flac. But not like MP3s would be. We're still talking about lossless audio after all.
On Macs, you can just copy & paste the raw AIFF files right from the CD. You'll probably want to run those through Toast too, just to keep everything nice & tidy and in Alac format though. But AIFF will play just fine in iTunes and everything just the way they are.