They are great if used properly, but personally I prefer gentle leaders or martingales

As long as its not hurting your dog, use what works for you. Don't worry about what other people think because 1) it's not their dog, and 2) is therefore, none of their business.

Prong collars are abusive if they're used wrong, just like flat collars. There is such a stigma around prong collars and e collars whilst dogs die from asphyxiation pulling on flat collars... i used a prong on my springer, now i walk her on a flat but she walks nicely, even so i always have thick 5cm wide collars on her so there is even less risk of injury. Of course its important to remember it shouldn't be a crutch, its not a collar like i see bully breeders use it as, its simply a training tool that should be phased out for a collar or a slip or something simular :)

I have a goldendoodle as well! She does great with a prong collar! Once they understand that you're in command, they will easily walk with a prong. It might look as if the prong hurts them, but it's actually a great training tool! Your dog is still a puppy, and must act like one too, but once it can understand the ways of training, the prong collar will help tremendously!