That railed handguard looks longer than 12". LMT's website doesn't offer much in the way of detailed specs, like rail length, weight, barrel profile, etc. The barrel profile appears to be fairly light, but can't tell for sure in the photos. Where's the balance point of the rifle with a loaded or unloaded PMag?
I really like the extra weight of the UBR with the 20" tube of my 308. It balances at the 3rd from the front rail slot on the upper receiver (with irons). With a 16" barrel and SOPMOD, your probably points pretty well.....just somewhat heavy compared to an AR.