+++for Kevin. Slings are for carrying, not for close quarter combat, particularly not for HD. A long gun needs a sling for lugging the gun around, or for letting it hang like on a fixed post. In HD, it will just catch on things and hang you up at the most embarassing times. Yeah I know, dropping the long gun to sling position to get out your handgun and start blasting like Steven Segal. Even that will be easier if the long gun is totally disgarded, and you would only disgard a useless(dry or jammed) long gun right?
That being said one of my Stoeger coach guns has a sling(like Kevins, with QD swivels) so I can shlep it around the back 40 easier, the sling comes off when the gun goes back into the coat rack at the back door.
The sling swivel studs are attached in the normal manner on the stock, and tapped/screwed into the barrel joint just forward of the forearm, using a diamond shaped plate for the stud available from Brownells.