Rehab centers, sports clinics and chiropractors use this a lot. So do some acupuncturist . Actual success with trigger points would only seem logical; as releasing the knot/blockage and allowing the natural path of the nerves and blood flow. Those home machines are pretty cheap, though may have to be familiar with the pro's and con's of using it first. The professional models offer a better choice and range of settings I have been told. And the look cooler. The human body is a electric magnetic generator anyway, so should respond in kind.
Have had great success with acupuncture over the years for potential muscle nerve alinement/flow problems (knots). Sports massage or Rolfing can be very helpful, but be warned both hurt like hell. No pain, not gain I guess.
A good friend of mine, who is a veterinarian, uses electric methods like STIM on animals. Haven't heard one dog or cat complain yet. Good Luck.
One of the girls in my lab brought one in for me to try. While providing some temporary relief, the unit was a higher-grade one for which she actually required a Rx to purchase. I am going to look into obtaining one for myself. I'm quite curious how I may benefit from consistent use.