Supposedly the whiter your skin and darker your hair, the better. I was good candidate according to that caveat.
I had my back and shoulders done at LaserAway Hair Removal Service (a company throughout CA). I had mixed results. Shoulders didn't take to it and my back didn't completely go away; the hair just became finer. That's with 8 sessions/treatments (cost was about $2000). Note that this company also throttles their lasers during the summer, so the intensity and efficacy of the treatments are diminished.
Kind of a gimmick with them as they wanted me to get another 6 sessions. I passed. I'll stick with the razor now.