Preliminary That said - and I agree with the other recessions - the training DVD is not really helpful, but it is a promotional DVD, probably a few exercises are shown on only these are in any case recorded on the poster.
The Black Roll is made of hardened plastic, is easy to wash and skin-friendly.
The Blackroll itself is ideally suited for large muscle groups (legs, back) and a pre-massage for general relaxation. But for smaller muscle groups and for intensive massage or to loosen adhesions in the so-called trigger points, I recommend to use the Black Roll balls. On the one hand to get easily ran with them to the trigger points, and on the other hand you can then yet exert more pressure. Initially, this type of massage is painful indeed, but after a few applications, the pain eases.
Personally, I was able to reduce muscle tone especially in the neck and have since often less tension in the neck and headache.
It is important when using the Blackroll that before the massage, the body is warmed slightly and all muscle groups are stretched according to the massage. Only the self-massage alone is not sufficient to release the adhesive bonds.
All in all I would recommend the Black Roll, even if the price is a bit expensive but for a few pieces of plastic with 50. In addition, the Blackroll can never replace a visit to the masseur alike.
Tip: In Youtube there are a few extra videos to apply the Blackroll or Blackroll balls. In addition, you should again keep close track of the trigger points in the body.