Ive broken couch mounts, cold fusion, rhass, oem.. But ive never ripped an insert out of my hull. So id rather replace a motor mount or 4 than deal with that.
Ive been running 6 mounts for a few years now. I still break them sometimes, but its usually only one of them at a time and i just swap in a new one.
I stopped using kenney keepers when I switched to 6 mounts. They just kept breaking, bending, and became a hassle. I even bent the billet freeride innovations ones. We also made rear kenney keepers to help from smashing the midshaft back into the housing back then. I guess i got a little smoother with my riding and havent had those issues anymore.
Been using RRP mounts in my flatwater ski for the last 6 months. They seem pretty good so far. Way less vibration than a cold fusion mount.