As long as you're using a lossless codec you should be fine. Why not try a little experiment and rip to a lossless format yourself? Then play it back, A-B'ing it against the original file.
I am quite satisifed with FLAC, and I can hear no difference between that and the original WAV file. Give it a try and report back to us what you hear...
Best Wishes,
-RW-