I believe the new Aero Precision lowers have nylon tips on the set screws. Softer than metal. Would allow some compression for a tight fit.
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I have one on my LWRC IC, after I finally figured out what it was I tightened it down a bit. To your question, yes it works. But I felt like it made it more difficult to pull the take down pin. Not a big deal, but I have to tap it out with a piece of plastic and a wooden hammer. Wouldn’t be good in the field.
I removed the nylon tipped tension screw from my Northtech lower. There was no compressing the nylon, so all it did was make it harder to disassemble.
I’m doing a build with a Rainier forged lower and upper. It came with the tension screw but the two halves fit so nicely together that I see no need to install it. If later on it ever loosens up, I’ll consider it then. Now on my 20" precision build, (Should get started on it this weekend) I’ll be using it for sure. I want everything to be as snug as possible.
I thought a small amount of play between the upper/lower was acceptable because as the gun heats up the receivers will expand slightly in size.
Bingo. Just TRY to break open a hot 6920/et al after a summer training sesh with an accuwedge or one of these devices.
I want to watch. 
Rainier has decent receivers. The tension screws on their receivers are completely superfluous though; unless something has changed, their uppers/lowers are so close in tolerance it gets difficult to pop the takedown pins after moderate sustained fire.