Used to use Sonique, but there's one thing that made me go back: the playlist handling.
I have ~1200 MP3's, and Sonique's playlist function just cant handle it very well, its too slow, and the quick select doesnt work as smoothly as Winamp's does.
Sonique has better sound though.
Since I changed from a SBLive! to a Sonic Fury(Same as TB Santa Cruz) I've been using Jet-Audio that came with the Fury, very good sound quality and the quick select function is sufficent.