I use a widowmaker which isn't made anymore bur the closest thing is a ez grunter. Reason being inhale and exhale operation, produces excellent toned tending or huffing grunts but like kevin freezing up is the main benefit for the colder climate hunters.

HS truetalker is the easiest/fastest all in one, though quite large.

The can is a simple, bleat sound that can be used at any time andhas the potential to work really well near the rutting stage.

I only carry a grunt tube, the other sounds I make via voice just as well as any call I have heard produce.