I just posted this on another thread as well, but the Nibble Net Extreme is very sturdy. I have two mounted to my horses’ outdoor shelter. The top rings are attached to eyebolts with double-ended snaps and the bottom corner rings are tied with baling twine so they don’t have access to the back side. They’ve been out there for well over a year with minimal damage (they did tear one of the corner nylon straps that holds the ring so one bottom corner is no longer attached).
My mare is so aggressive that her Porta-Grazer had to be taken away. They were tied to the shelter so the barn help would not have to go out into their paddock to retrieve them. There was just enough give that when it was empty my mare was able to bash the Porta-Grazer against the gate. Loudly and for very long periods of time 
