WA5 is pretty good, IMO. It eats a bit too much CPU while playing WMA 9 tunes, sometimes upwards of 50% on my P4@1.7GHz box, but sometimes it's less than 10%. Seems like a bug to me.
Other than that, I don't have anything to complain about. The media library is abhorrant, but I'm not forced to use it, and I can control the player with my keyboard's media keys. Very convenient.