Very subjective. The generalisation is only correct when comparing to Xing type MP3. However when comparing to LAME you'll find on low bit rate WMA (e.g. 64kbps which is supposed to be the equivalent in quality to a 128kbps MP3) is noticeably worse, even without headphones, because so much of the treble detail is lost. IMO MP3pro makes a better job of lower encoded files, but then of course MP3Pro is not a widely supported format. I don't know at what bit rate WMA does starts to begin to come into it's own, but I shall be experimenting with WMA in the next couple of days just out of curiosity