To me unless you plan on patrolling for long periods of time with your rifle/carbine in a horizontal attitude I see no real advantage for a 3-point sling. If you do, the Spec-Op SOP Sling with TRB is the way to go…
I do have a CQB Solutions ‘CQB’ sling for my Standard Model M1A, but I can't see ever doing any room clearing with that rifle. If I was doing any room clearing it would be with my M4gery.
My AR is a pre-ban Colt Sporter Match H-Bar, but it is mostly in a carbine configuration with a 16" Bushy M4gery upper.
The only reason I want a sling on my AR is for worst-case scenarios. An armed confrontation leading up to, engaging in, or averting a gunfight will be a very stressful situation. I will be in an adrenaline pumped state and many unfavorable physiological reactions that come along with that. In addition to adverse environmental conditions (rain, hail, sleet, snow, extreme heat, low visibility, blinding light, etc…) poor physiological conditions (injured, exhausted, colt, wet, dirty/muddy/slimy, hot & sweaty, etc…) It’s likely I might bump into something unexpected, fall, or just plain fumble my weapon and I don’t want lose it. Furthermore if I run dry or have a type-III malfunction I can simple drop my rifle without losing control of it transition to my sidearm to stay in the fight until the threat is neutralized.
This is why I like my CQB Solutions MOUT QD sling so much, KISS… It mounts cleanly on the weapon with a receiver end plate adapter, I choose a GG&G rectangular plate. With the MOUT there is not much to get caught on thing as there is nothing forward of the rear of the receiver. Transitions from strong to weak side are seamless, and the weapon is secure. If I need to climb a ladder, jump a fence, with a single point sling I can simple rotate the sling around my neck where my weapon is on my back to climb. Additionally if I must get away from my weapon if it did snag on something, or I need to mount / dismount a vehicle I don’t need to climb into/out-of the sling and have it possibly get caught up on anything on my tactical vest, I can just simply disconnect/reconnect the fastex buckle…
Just my $0.02
Good luck on your decision,