I still maintain that the ms2 sling is probably the best thing magpul ever put out in terms of airsoft usage. (I don't bang bang, only pew pew) My only complaint is that the tubular webbing used feels awesome and doesn't chafe but the tradeoff is that it has a tendency to roll and flip through the hardware or it's so slippery that it needs to be constantly adjusted.
Even the fake ones tend to be really good.. how can you fuck up generic tubular webbing and steel sailing shackles that have been around for decades?
The ms2 is a 1/2 point convertible, so as long as you have sling loops to shackle to, you can run it as a 1 or a 2 point and change very quickly.
ms3s real and fake have wideass standard nylon webbing that digs into skin, giving up comfort so that the webbing can slide through the glides and loops properly. The proprietary magpul clips and shackles are pretty bad, you can't beat steel shackles, and for some reason magpul went with some proprietary nylon with fiber reinforcement to cast/injection mold their attachments. They grind/wear with time and I'm pretty sure I've read of a few failing. Knockoffs fail within weeks of serious use and will drop your gun.
I futz with V2s, V3s and V6s. I could be wrong... but probably, most likely not, as far as I know.