got it half right.
There are two connections. The Olympus lens to adapter, and the adapter to the EOS camera.The connection between the Olympus Lens and the adapter is nice and tight but the connection between the adapter and the camera is not tight enough. You can feel a very small wobble when applying pressure. I tried an EOS lens and it was snug; no movement. I tried body caps and they are tight so I added a shim. A piece of paper .003" thick and now it is snug; definitely not too tight...just snug. I do believe the oly side of the adapter is an improvement over the previous brands but also believe that the other side needs fattening up a few thousandths.