I know they work and I know that some people swear by them. Personally, I don't like using them. We are required to use them at the Pound for all the dogs that come in (with no history on the dog, it is difficult to work with anything else), but on my own dogs, I don't. (Once I've worked with a Pound dog for about a week, I will usually switch to a martingale collar, but that is another post!)
I like using positive methods - such as rewards - for proper heels and not pulling on leash. I know a lot of people find that the quick-tug works for their dogs. Although it can work for some dogs, it doesn't for others. Each dog is different and training should be different for each accordingly.
Personally, I have found that the quick-tug doesn't work well for many dogs and have had much more success with more dogs by using positive rewards (toys/treats/etc).
Do you use a choke chain? Have you used one in the past? Would you consider using one if you ended up with a large dog (possibly close to the same weight as you?) that was reactive on leash or would you use something else??