The Heriba is very clever, it does two important things that a capo should do: lets YOU decide the pressure, and does NOT move the string sideways when the pressure is put on. So the Heriba won't pull or push anything out of tune.
Heribas used to be indestructable, but some years ago the manufacturer started using a different kind of rubber for the (separate) part that presses the string. Now this part lasted just a few days. I can only hope that quality control has noticed this (SERIOUS) problem. Do not be deceived by its plastic looks, the Heriba is a great capo. The Heriba is not the best choice for high tension (acoustic) steel strings, although the clever design will nicely follow curved fingerboards. For nylon strings guitars: recommended.