From what I recall, all of the SAWs we went down range with had either an ACOG or a CQO on them. My experience with them is limited to basic qualification, ~500 rounds, which was a blast, but other than that, all I can say is that the shortened "paratrooper" variant is about useless past ~175 meters.
NRA Life Member
Big Sister: "You should be sponsored by Allen"
Me: "If you can't shoot good, at least look good walking to the firing line."
Big Sister: "Can you not afford a Pelican? Then buy an Allen gun bag."