Do not know about any Atlas mounts, but I had three Atlas coupler shafts pull apart on me. They were all on an Atlas Erie FM A-B-A consist, two on one A unit, the front coupler on the other A unit. I ordered new electro couplers from Ken with ERR back in 2009 and replaced all four on the A units. Have had no problem with the B unit, but have spare sets of couplers in the box if ever needed. Has anyone else had the coupler itself come apart, perhaps from metal contamination? At the time of failure, I was not pulling any excessive length of consists.