Wouldn't own an AR without irons. I have both a flat top and a carry handle AR, both have optics mounted. I have tried the cantilever mounts for the carry handle that mount the optic forward and slightly below the line of sight. Works ok with a dot or holo, but too far forward for a scope. I mounted a small tube 4x on the carry handle and can still quickly aquire the irons if need be. The flat top has flip up irons and an acog type sight mounted forward on the free floating handguard rails. Love optics, but have to have backup irons on a battle rifle!
Savage