The signature is a 16" barrel with the FF tube ending at the end of the barrel, so you're correct in what you said. The hadguard does not act as a flash hider. I guess you could add one of those to the barrel, but I couldn't tell you if it would fit between the crown of the barrel and the inner part of the tube. There is no sling with the upper, but it does have what I suppose is a bipod stud and another threaded opening for a sling swivel. If you expand the picture at Kiesler's web site (http://www.kieslersonline.com/product/ko_specials.asp) you can see the stud and hole. Cut and paste, I'm too lazy to use board code, sorry. I do plan on putting a harris bipod and sling on mine, I just haven't gotten around to it. From the bench, I can put 5 shots into just under an inch and a half at 100yards and standing three inches, but that's just me. The rifle could probably do better. So at 200yds you could expect 3" groups. Again I'm very happy with my upper and have just put it on one of Pete's RRA lowers. Nice match.