Picked up a J&T Chrome lined M4gery profile barrel & kit last year. (The one with the kick ass muzzle break that looks a lot like the standard f/s).
I've got about 1000 rounds through it, and let me tell you -- I love it.
Not a single jam yet. (True, I am religious about good magazines, but still).
Mine shoots sub MOA if I do my part (which, unfortunately, isn't often these days as my eyesight goes downhill).
My typical group with open sights: 2.5 - 3.5 inches at 100, off sandbags using Lake City. A lot of folks can do better, and the rifle is surely capable of it. (Never scoped it up, so I can't tell).
Be aware that once you go to chrome lined, the finish will be parkerizing and not black oxide.
Still, very cool. J&T uses a nice dark park finish. I like mine alot.