Decent acog mount with a couple drawbacks - American Defense Manufacturing AD-B3-C Cantilever ACOG Base

So the good, it's a comfortable height and it's high enough to use some of the rail underneath. This mount obviously is far less robust than the stock Colt style mount, and the clamp and whole mount isn't as good as the Midwest one, the clamp in all honesty sucks sticking out so far and might bend or break far easier from vertical impacts. Only buy this mount if you can't physically get a proper sight picture or need the extra rail space, otherwise it's not worth it at all and looks rather goofy installed. A piggybacked RMR would also sit too high using this mount imo, so you'd want to run a offset sight and then lose the weight savings over the Colt style mount. The stock Colt style mount or Midwest mounts are likely the best options for the vast majority of people.