A primary difference between the LaRue and the ADM, the LaRue (SPR-E) will allow the Shepherd to be placed forward enough on the receiver to just barely allow the use of my Troy rear BUIS, where as the ADM will not. But with my intended usage, it is not a problem.I mounted both of my Shepherd LPVOs in QD mounts, one a LaRue and the other an ADM, both have been very solid and satisfactory.