It all depends on how you take care of your calls ,I hunt sub zero weather,and dont have a problem with freeze up.I do carry 3 calls on each lanyard and when calling in cold weather,keep the call close to your mouth from start to finish,and when not calling put just enough air through the call with out making any sound,then when moving to your next set put your call inside your camo next to your body to keep it warm for the next set,Now moisture build is another thing, thats the reason for the other calls,along with differnt sounds.With a open reed call freeze up is no problem cause once the call is in your mouth everything thaws out as soon as the sound board is in your mouth,no matter the temp.The gum up problem can be solved by staying away from drinking POP,or any sweet stuff while calling,Ichew 1 piece of gum all day once the sugar is gone your good to call.The other thing about moisture,is a good wood call will tolerate more moisture than a plastic one