Call Ducks are excellent fliers and if they get away, may not come back. There's no risk in clipping the feathers on one wing to stop them from flying, because the feathers do grow back after a molt. And I'm not aware of any medical benefit to allowing them to fly, only danger from them escaping. I lost a new East Indies show Duck when the breeder shipped her without clipping one wing and she escaped in the pouring rain. We tried for an hour to find her but gave up and never saw her again
As others have said, Call Ducks are VERY NOISY if you get females! You really need to hear it to believe all that noise comes from such a small cute bird! In the mornings when I go to the barn, till they are fed and have water, you cannot even hear another person talking because of the Call Ducks! If you want a more quiet duck, then you'll have to get two males. The problem is that none of the hatcheries will sex Call Duck babies because they are too small, I assume it makes it impossible to be reliable. So, to get two males you'll either need to raise 4-5 Call Ducks and rehome the females or buy them as adults. In my experience, those raised by others are never as friendly as the ones I raise myself. You might also consider male Indian Runner Ducks. Mine have much more character and are absolutely hysterically funny, compared to my Call Ducks. People say their Indian Runners are nervous, but mine are super friendly and curious. They are gentle and comical, in my experience. I have: Pekins, Cayugas, Australian Spotted, Snowy Mallard, East Indies, Butterscotch Calls, White Calls, Gray Calls, White Indian Runners and Penciled Indian Runners so this is what I'm comparing them to.