I've shot them on several rifles since the 1990's.Never had an issue with them returning to zero or anything of the like.They have been used on 5.56,6.8,and now 308.They can occasionally be found used on AR15.com Equipment Exchange for less $$.Like all equipment thorough and proper use is essential.My most recent 308 AR turns in slightly less than MOA with my reloads and the LaRue mount.Removed it to put on a Comp m3 Aimpoint for awhile then replaced the MK4 with the LaRue.No noticeable change in POI,YMMVH