I used to change my players on a weekly basis as was never satisfied with RP. I was recommended Jet Audio and now use nothing else to play any format of audio file. HIghly recommended, it is a fair size download but well worth it.
The only other player I have is musicmatch which I use solely to convert to mp3pro. These are half the size of a standard mp3 but with no loss of quality. Convert a wav to mp3pro at 40kbps and it is roughly the same size as an RA but the quality is far far superior.