Hopefully this reaches capable and competent eyes,

I'm interested in purchasing a new sling for my next tour/training. I'll be running with an M16A4 with M203 attachment. I have been eyeballing all of my tac sites, Google stalking any sort of answers, but I haven't come across a quality comparative review featuring this particular setup. I have always been a 3-point sling user by default, whether it be gear issued or bummed off other Marines, but I have also heard very good things about switching over to a 2 point. I am an open book looking for input, the VCAS 2 point and the Specter CST 3pt have caught my eye due to good reviews, but I am looking for some more input. Keeping the operation of the grenade launcher in mind, and also the fact that I shoot left handed, what is your suggestion for the optimal sling to use?