http://www.mp3-box.org/mp3-sound-quality-comparison/

Do CDs ripped with FLAC really sound that much better than high quality MP3s?
I’ve noticed that quite a few audio snobs are now saying that ripping audio CDs in FLAC is the only way to go. They claim that even MP3s ripped at 320 kbps sound compressed in comparison. Is any of this true?
I rip all of my discs into MP3 format at 320 kbps and can’t tell a single difference between them and the actual CD. Besides, discs ripped with a FLAC encoder are massive in file size. Even a 1 terabyte hard drive wouldn’t be able to hold too many albums. What’s the real deal here?
Only way you’ll know is to listen to one of each for yourself. Some people have better hearing than others. Personally, I don’t bother with anything higher than 192kbps. I can rarely tell the difference on most of it and don’t really mind too much.
Honestly, I think most of the people yelling about FLAC are just doing it because they think it makes them sound cool. They probably can’t tell any bit of difference at all.
I’d say if you can’t tell the difference yourself, don’t bother – especially considering that not a lot of audio players even support FLAC.
Audio Comparison: Flip Ultra HD Mic vs. Zoom H2