I am also not a fan of a prong collar for many reasons and in almost 25 years of working in Rescue plus in Training/Behavour; I can count on one hand the number of times I have ever used one and twice was on my own Goldens, my own – brothers and then only used for couple of times and the dogs 'got' it and I then could move to a flat buckle collar as should the be goal of any one to be able to walk on loose lead with your dog in a flat or side release collar. I have not used a prong since 1996 in my own programs.
So many Trainers(and I use that term loosely for as many know, this area is a pet peeve of mine due to the complete lack of regulation surrounding the profession) do not teach the owners how to properly utilize a Prong and then there are the owners and also trainers that use the prong as a 'crutch' or 'quick fix' instead of a temp measure(and that really should be defined) as the owners do not work towards the ultimate goal of moving away from what I call a 'teaching tool/aid' of the prong to the flat/side release collar.
I see so many Giant Breeds in prongs and many of them puppies 
and I continue to try and educate plus make that difference where I can to those that ask or would listen. In working in Rescue, we often get those 11 month, 18 month old, 2 year or 3 year old untrained, jumping, pulling, yanking, jerking etc. Great Danes and all have learnt through time, effort, patience, consistency with positive training/guidance and leadership to become assets to not only their home yet the community and this sans the use of a Prong collar. Additionally, as part of our adoption contract, there is an obedience clause whereby each home must take their new adoptive addition to a full round/session of obedience classes to carry on this training, creating a great bonding opportunity PLUS it is a great social network for both dog/human. Lack of training is one of the top reasons why we have Great Danes surrendered to BHRR and when many people realise they can no long 'man'handle these dogs, they look to myself as a Rescuer or as the trainer/behavoural expert to assist them.
Trainers need to train the owners how to continue the training at home and outside of class or training sessions.
I have seen much damage caused by the improper use of prongs in not only Rescue yet at the Hospital.
Choke chains can and do cause its own share of damage to a dog.
Nothing should be used as a quick fix or a crutch in place of a proper training regime and program. In March of 2010, we had an addition to our BHRR program of a very obese 191.80 pound 2 year old female Great Dane(with two blown cruciates) and when she first arrived if she wanted to go somewhere, she took me along for the ride. Even with her 2 blown cruciates she just walked off with me attached to the lead(what little walking she was capable of doing with her weight/cruciates). Less than a week later and she was walking wonderfully on her flat buckle with me. 
My time, consistency, routine, repetition, commitment to her training has made the difference. I use both treats and praise and through time, weed out the treats or toy and while they still get them here and there, they never know yet praise is always present.
One thing that I learnt very early on is that 'common' sense to me is not to others and all of us could and do benefit from going to a proper and certified trainer. I know I still do with some of my dogs just because and even with the training plus education that I have; I still learn things, good things when I do! 
AND I live quite rural and it is not unknown for me to drive up to 1.5 hours or so one way in good weather to attend classes taught by others! As has been mentioned previously, 'IT is that important'.
I also will say that what will work with one dog will NOT always work with every dog. One has to be resourceful and if one method that has been truly tried does not work, another method might. Yet you have to give that method a good shot first. I find some dogs do better with their show collars over a flat and others work better in a martingale yet prongs nor choke chains are not used in the classes I teach nor with my private training and/or behavoural clients.
The term 'correction' has often been related to 'punishment' for many people and trainers yet I always use the word 'correction' as being positive based.
JMHO FWIW as always.