With Sportsmatch ATP61 & ATP66 adjustables I have had no problems at all (i.e. they hold zero perfectly). Just ensure that the reversable clamp jaws are set correctly for your dovetails. Also a good idea to degrease the jaws and the dovetails prior to fitting.
Another alternative for you would be an AJP Engineering riser rail which can be custom made for the moa adjustment you desire and also for the specific mount which you plan to use.