I've used the Dubro mounts and really like them. They will let the engine bounce around a slight amount, but they do a good job at what they are designed to do.In the event of a vertical landing, they offer some protection to the engine. The only issue I've had with them was on a plane with a Mag 70 four stroke. It was doing some strange things on take off when I would punch the throttle. The plane would pull to the right. Ifinally happened to be standing in the right spot when the plane was on the bench and saw what was happening. On hard acceleration, the engine was kicking a couple degrees to the right and down about a degree. I found that one of the aluminum spools was shorter that the rest and I was effectively setting on a chair with one short leg. It wasn't much, probably less than a 1/16" difference, but it was enough to cause a problem. Ireplaced the spool and all was well.

I've yet to try one of the mounts that require a nose ring on the engine. Those allow the engine to torque, but hold thecenter line. Any movement onthe Dubro will slightlyshift the center line.

Don