If you are using them properly, the material and type of grip isn't as important as you might think. Most of the weight will be supported by your wrist using the strap, so the grip is really just to pick up the pole and place it again. So pick one with the comfortable wrist straps, not the most comfortable grip. I don't really notice much of a difference between the soft foam and the hard plastic grips on mine.
I agree the "proper" way to use poles is to heavily rely on the wrist straps. Manufacturers/pro-staff give instructions about proper strap use in line with the above, and I'm sure it is more efficent. I just don't like the feeling of a properly tightened strap. I think because I feel like my hands are tied. While they really take strain off of hands and forearms by reducing grip pressure requirements, I just don't like the feeling.
For me, grip material is very important. To each his own, for sure. Everyone's different and you gotta go what your comfortable with. It's awesome to see different takes on things!! Helps us all find what works.
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