Very good product with good adhesion.
I covered the panels of the car doors after first installing sound-absorbing panels of 4mm internally in the doors (on the metal).
The micro-vibrations in some areas of the panels were also reduced, resulting in better sound quality.
You can perceive the difference, but don't expect dramatic results.
It definitely does the job it is intended for, and I recommend it.

It does not have a strong adhesive base. It does not cut easily with scissors. It also tends to "rub off" at the cutting points.
It is probably a general-purpose insulator. I do not have an opinion on sound insulation yet. Overall, my impressions are rather mediocre.