I have 3 very large german sheaperds who like to bark. They do not bark at nothing, they bark when they play. They like to herd things around and bark at them, especially when they are getting attention. At night, not a peep unless someone comes in the driveway. I almost tried the collar, but a few weeks of training worked pretty good.
Here is the straight up, if you have a dumb dog, get the shock collar. It works fine and does keep dogs from barking excessively. After one or two shocks, turn it off but leave the color on. Things to remember, clean the contacts with alcohol often to avoid giving your dog dermititis.
If you have a smart dog, be careful with the collar. It sounds wierd, but you can cause a little phycological damage if a dog barks for multiple reasons, but cannot associate the shock properly with its actions. Smart dogs are more emotional, dumb dogs just take it. With an intelligent animal, there are other ways to get them to stop barking, like saying "no". If your dog cannot associate commands, try some basic training (usually intended for show dog bull****) for a month or three. 30 minutes a day for 8 weeks will do wonders for a dogs behavior. Many community centers and city activities, even in the boondocks, offer these services.
Or you can be a complete a****** and just remove that larnyx. That's humane.