apple for me. I've tried cherry and hickory, but can't seem to get a good flavor of of them..fresh dried wood too, not store bought. Can't miss with apple though. Did some chicken with apricot, and that turned out pretty good too.
Charbroil gas, 22.5" Weber, UDS, Mav. ET-73, Thermapen, iQue 110, Weber Go Anywhere, Lg. BGE