I just got mine and have had about half an hour to play with it, but holy shit does this sound great!

http://www.xotic.us/effects/bb_plus/

It really thickens up and boosts the tone for solos. I've been using a Danelectro Daddy-O - don't laugh, it was the only box that sounded good and gave my Fender Prosonic a noticeble boost - that sounded really good. But the BB+ is a whole 'nother level!