You can try the bark collar, it’s a tool, and if you want to approach it that way then it’s available. I don’t believe it will work in a situation of high reactivity and lack of obedience, unless it is stimulating enough to overwhelm the issue, which seems kind of like using a hammer on a screw. Will it work? Sure if you hit it hard enough, but there are more forces at play which require a more sophisticated approach. Do what what you have to if that’s all you can do but it’s not the best method. The best method is going to be long and hard, which is to take the approach of training, using behavioral psychology to condition new behaviors. The collar just uses a punishment to discourage a behavior. To use the book 1984 as an example, shock someone enough times and they’ll tell you 2+2=5 out of fear and compliance. But what big brother wants is for you to believe that 2+2 really does equal 5. Any behavioral modification program should be shooting for the latter. Back to the basics, conditioning from a distance and redirecting/punishment towards low level stimulus like a perk of the ears, not up close under full reaction. During the training period you can never go backwards, and never put them in a situation that they aren’t mature and trained enough to handle, which will create inconsistency and failure in the training. This means that if you can’t control the situation, the pup shouldn’t be there. This will probably take many many months, developing your approach and the scenarios you use to train on a weekly basis, if not more, as you evaluate the next appropriate step during their progression. I put probably 2 hours in every day for 10 months with my Dutch Shepherd in order to get her to not be reactive, and now she’s perfectly neutral…but it was a rough time. The differences in approach will be seen in the way other behaviors manifest themselves in other situations. Every approach has it’s consequences or benefits, even if the primary issue is solved to your liking.
If you don’t have the time to train, maybe the collar will work, for now, in the context he associates the negative experience it with. But it won’t give you the same behaviors and personality/relationship a dog will exhibit if they were trained the “right” way, which is to say with modern behavioral psychology. That is just my humble opinion. At the end of the day you have to do something, so the collar is better than inaction. Good luck