I love Victoria, but again, it depends on the dog and how you use any device or training method. I watch people all the time calling their dogs over and over then punishing the dog when it finally does come. Yeah. Let's punish the dog for coming.
If you are going to use a shock collar, vibrating collar, spray collar or any physical device you must use it properly and be with the dog to see how he or she reacts. If a spray collar worked, and somehow the dog associated the spray with something stupid, you would get the same bad result with no shock.
As for the device on Amazon, look close at the reviews. There are a lot of 1 and 2 star reviews. As I've said, I did a lot of investigating and tried a lot of products before resorting to the shock collar. Actually, it's called a "bark control collar."
Anyway, how does Victoria control barking? Ceasar would have you walk the dog till it was too tired to bark, or you were so tired you didn't care.
And trust me. I only use it when I absolutely have to control his barking. He's normally quiet, but he barks plenty when a dog should bark. Anybody who knocks on the door would swear I have a Pit Bull in here.