Personaly...I'm in the middle of having to buy a whole bunch of job related gear, right now, which precludes me from spending any more money, on the FN-TPS for a couple of months.
All I have done with mine, sling wise, has been to cut down a old Uncle Mikes nylon sling that I had laying around, until it was just the right size to make a "13 double loop through the upper and lower sling slots of the telestock. Making a handy shoulder loop.
This rests the shotgun down your right side, with the barrel spending entirely to much time pointed at the toe of your right boot and is kind of a mess, if your wearing a pistol holster on your right hip, when you go to a shotgun/pistol transition, unless you just flip the shotgun all the way back past the holster.
The good news is, that it rests the right palm handily on the pistol grip and the loop swivels the telestock, with it's rubber CAR butt pad, on to the shoulder, quickly and effortlessly. as I said before, you just find yourself with your hand on the pistol grip a lot of the time to keep the darn thing pointed off your boot.
Now you may ask yourself. Why would you go with a set up like this, when you have a perfectly good sling swivel, on the end of the FN-TPS's long mag tube? The answer is...Because I dont like sling set ups on shotguns,
that allow the sling to swing up in front of the barrel, while firing! Having your whole sling set up, come unglued, as you blast it apart, about the second shot, would be pretty distracting, if you were using the TPS to defend yourself and I don't like distractions, that make you ask yourself, "WTF just happened to my weapon." In the middle of a fight.
The FN-TPS screams for a single point sling set up and the good news is, that several makers, have come up with AR-15 single point sling mounts, that do not require removing the telestock tube. (GG&G, Midwest Industries and Daniel Defense come to mind.) One of these, combined with a Spector (formerly CQB Solutions.) single point sling. Is the route, I'm going to go, once I get all the other stuff that, I suddenly had to buy for my new job, out of the way.