I may not be an expert dog trainer however up to and until I got very sick many other waterfowl and upland bird hunters were in awe of my dogs for a gentle mouth and a willingness to retrieve .
A shock collar is a great aid in a hunting dogs development or even if it's going to be a family dog and never taste feathers . But like anything you need to be aware of what it can and can't do training dogs can be as easy or difficult as you want depending on what you want for a final product if you would .
My last dog knew when the shock collar came out we were going to work ( Hunting ) and during what turned out to be his last trip hunting he acted like a puppy on the first brushy draw sadly no pheasants were shot it was great watching him work the cover .
In other words don't buy a shock collar and expect it to turn a poor mannered dog around instantly you will also have to do your part in teaching the dog what it's job is , here's the tough part you have to be smarter than the dog ha ha
Some folks on here are now in trouble ha ha