Ok you soft-mount advocates think about this, the engine,prop, spinner and muffler weigh around 4.5 pounds give or take depending on size and manufacture, its not at all uncommon for our planes to see +/- 12 G's and sometimes more. That means the mount must support around 50 pounds plus without too much movement. Sounds like one freek'n hard hunk of rubber to me. Also remember that its not the low frequencie vibrations that hurt parts and radio gear its the highs, so to work the mount would need to be soft enough to absorb these small movements. In most real planes the mounts are installed at angles, I wonder if they know something we don't?