Yentzen/Sure Shot made some duds. I've got several still in the box, that I got when my Grand dad died. I tried every one, and none of them sound much like a duck!
I personally never had many issues with Faulks. Matter of fact, if a guy has the ability to tune it to his likeness, they’re dang ducky. In really cold weather, they’ll hang up but those calls came out of LA and most folks further south prolly had no issues. Lotta great history between Faulks and Olt, for early mass production of affordable multi species game calls.