The new STX strut is more friendly to the mounts. The compression damping softens the landing much better than did the ST model. But I have to second what has been said that when running the struts to take the place of the bumps, you are placing all the load/force on the mounts. Standard shock mounts are not enough. It is best to distribute the load over a wider area, much like an axle truss does, but to a lesser degree.