For quite some time I'm Free athlete and have but now and then a few aches and pains with the muscles. By default, almost always in the neck. After every gym class I roll through once and since then it's much better to me. The muscles from the feeling even more resilient.
I can only recommend and in my opinion, a lot of cheap imitation parts are much too soft. You do not meet the original purpose or not long remain so stable from tissue. But that can each decide for themselves.
From me a strong buy recommendation for the stock!