How do you plan on using your rifle?
If you might shoot national match or want to keep the classic look of the M14 then go with a military sling. I have a Turners on my match gun and had a DPMS on my Socom. The DPMS is old and not that good of quality, took a lot of leather cream and work to soften up. The Turners is very nice and soft. I can't comment on the "1st Tier Slings" by TAM as I am only 2nd Tier. :(
If you plan to use it for more of a "tactical/action" style shooting or even hunting, then you could look into an adjustable 2 point like Vikings Tactics. You can get a buttstock adapter and then attach the front to the gas system or better yet attach a side sling swivel to the stock so you won't be torquing you gas system if you are using the sling for support while firing. You can get the padded sling from Viking which will help distribute weight a little better. This is the route I have decided to take with the Socom.
Utah1 - How is that ARMS mount working out for you?