A lot of us are using the AD Delta Mount. All mounts can make small marks on your rail. I have used La Rue, AD, and Bobro. Bobro mounts make the fewest marks. But if it is a SCAR 17 I'd use the AD Delta or a La Rue mount. If it is a SCAR 16 you can use any decent quality mount. I cannot speak to the LT111 specifically.