I like the VTAC sling on lighter rifles. I really like the wider KZ TAC II design for heavier rifles. I also got to try the SOB sling when I took a class with John McPhee recently, and if you like to mount the forward end of the sling out by your support hand and not closer in to the receiver, I think that is a good way to go.
That's all for rifles that are used primarily off-hand. For bolt action precision rifles, I make my own that work like the popular two-point, under-slung, precision shooting slings out there.
I run a Mountain Shooter slings, their design and construction is as good as any of the others I've used to include TIS, Turner, and TAB. Brock is a helluva good dude also. I've got one on my bolt gun and one on my 10/22 for practice.
I've used an old leather sling for about 12 years now, and the TAB sling is the first one that I've shot with that I really like, and i've shot with just about every "sniper" type sling across the industry.
I run Pat's slings ! on my tactical rigs and hunting rigs. He is now making them for the flush cups too I believe !
Highly recommend them. PGS is a sponsor here too ! </div></div>
+1 If you watch the GA vids in the Bolt Action Rifles section here, video 5 the GA non typical is wearing one of the montana gun slings and he shoots slung up with the same.