After about a week of my shoulders and neck being so tense that I was in tears nearly every day from the pain, I bought this massager completely on a whim. I wasn't sure it would be what I wanted, but this massager does everything I want.
It comes with a few switchable heads that pop on top of the basic heads. They are okay, but the different textures sort of hurt my back. I prefer to just keep the basic heads. The speed is controlled by a sliding button, from low to high. The high is very hard and can be incredibly intense if you are new to percussion massagers. Unlike how the title suggests, this percussion massager does not move, it is just an incredible intense vibration. It definitely works out the knots in my neck and shoulders though and that's all that matters. The longer you leave it on, the hotter the knobs get. This gives you an interesting sensation that some people may find very pleasant. All in all, I would tell anyone to give this massager a try.