WMA is supposed to be a superior format (at least according to Stereophile).
WMA appears to preserve more of the audio spectrum, while MP3s chop off large segments of the FR to maintain bit accuracy...is either better than the other? They are both pretty bad :P
But on typical multimedia speakers that have virtually nil response past 13KHz, I would venture MP3 is a superior format.
Either way, if you want quality, encode in FLAC...at maximum compression it's only about 50% bigger than 320kbps MP3...while retaining full CD quality. Of course, the more compression, the more CPU utilization to play the file, since all FLAC does is essentially crush the WAV file into a compressed form, and decompresses it in real time during playback. Most people use probably 1/3 or 1/2 compression to limit encoding time and reduce CPU overhead during playback, in which case the average file size is probably 15-20MB, probably 3 times bigger than your average 320kbps mp3.
But, if you have a modern computer...playing a FLAC file shouldn't take more than 1% cpu utilization, unless you are doing something intensive like 192kbps ssrc resampling.