well I have the Patrolman's carbine, that I sent to Kurt.  Originally it had a Mini Y comp attatched to the 16 inch barrel, so I sent oit to Kurt to have that removed and have one of his pressed on Fake FS put on to give it a shorty look.  I took it to Blackwater and ran it through a week long Advanced Carbine course.  Almost 3000 rounds in 5 days, no noticable over heating (ie never had a problem holding the handuards), plinking steel plates at 400 yards(iron sights), and I put a 6 inch group (30 rounds) into a man sized sillouete target at 300 m. using an Aimpoint Comp ML2.