I bought my DPMS .308 earlier this year, just in case.
That is the exact scope that I purchased. It’s a very impressive scope, no doubt, but I don’t have any experience with other tactical scopes to compare. If you wear glasses, like me, my understanding is that you probably want cross hairs like this one instead of a red dot type scope. Maybe it’s just me but I can’t see those red dots.
My DPMS rifle has a 20 inch barrel and it is surprisingly heavy. I might have considered a 16 inch if I had known that.
Have you considered getting the model with the detachable handle? I think the top handle on that one is fixed.
I'm growing older every day.
IMHO, you are better off with the longer barrel... you lose a lot of FPS and range with a short barrel in .308 / 7.62x51N. The powder load is timed for the 18” to 24” barrels, even the surplus.