I had some but after one low speed crash, the metal lock on ring snapped out from inside of the plastic of the grip, so the grip wasn't attached at all to the bars, and it just spun freely.
Also, even before they were broken, if I did something relatively big on them, they tended to rotate on landing, only slightly, but it was scary enough, this was because the screws really didn't allow enough tightening to stop this.