I ride a 163 Never Summer Cobra after only previously riding cambered boards. It's great in the pow while not being strictly a powder board - which I guess is what you want seeing you said all mountain rather that pow board.
Never Summer Cobra Snowboard 2014 | evo
Heard the Ride Highlife UL is very similar and has great reviews.
Ride Highlife UL Snowboard 2014 | evo