Does bark no more really work?

My next door neighbor has three dogs who constantly bark and howl. It is really annoying. I've tried talking to them about this nuisance but they refuse to open the door. I've thought about purchasing bark no more. My co-workers told me that this device really works. However, I am skeptical due to it's cheap price. Does this device really work? Our apartments are separated by a thin wall. My apartment door is directly across from their door. If this device works, where should I put the device?