[U2Lynne]

If you are extracting audio on a Mac, use XLD. It is the closest you will get to EAC. (I did some tests and got wav files with the same fingerprints as those I did using EAC.) Don't use iTunes and don't use xACT. The link to XLD is in my signature.

aiff is the same as wav only on a Mac it says aiff - simple as that. You may extract to wav or aiff, either will convert to the exact same flac/shn/ape file. Use xACT to convert to flac/shn/ape and to create shntool st5s or flac fingerprints.