I have some leverage sticks that have little to no "bite" on a tree. I don't get this complaint. The bit isn't what holds your weight up, it's the rope going around the back of the tree that hold the stick there. Not its ability to bite into the bark. I only want my sticks to have enough bite to hold the tension that I applied when I slid the stick down as far as it would go and not slide back up. But honestly, i've climbed some beach trees and my leverages don't bite at all on them. But, I have never had a single problem with them. I want to use the most minimally invasive option I can. I don't want sharp stand offs.
YMMV