Check out Tony Cowden, he just pick-up a couple of these and has been posting on his instagram about them. https://www.instagram.com/p/B_cjMhZJ6DB/?utm_source=ig_web_button_share_sheet <- SAS II SL SAW
https://www.instagram.com/p/B_mvMCypHrM/?utm_source=ig_web_button_share_sheet <- Open Gun
I have an Aero Precision FGC, unused and still in the package if your interested. It came in a Lower Parts kit, I already had another FCG so I didn't use it. PM me if interested.
These guys have just come out with a magnetic sling strap, don't know much about it other than they are selling out as fast as they can stock them. Neomag Sentry Strap
I have one in a pistol build, runs great no worries Super 42 Braided w/ H3 Buffer. That being said I haven't tried anything else so not a very scientific result, probably would run fine with a standard spring and buffer.
Never had any issues at all with the scorpions I've used, but those have been mostly the full length carbines. I would also recommend the AKV, the new generation has been great for me.