3 point sling are pretty much awful and, as far as I know, no trainers actually advocate their use any more. They are completely obsolete and, frankly, you can get the same level of "security" you're looking for from any sling system. I don't think you will find anyone with a VTAC or Magpul sling is afraid of their weapon "falling".
I use a lone-star single point sling, and have for many years. It allows me to shoot from almost any position and it has a quick release, in case it can't go where I need it. It also features a quick release for the sling, so I can take the gun off the sling, or the sling off my body.
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