Bruce, both are fantastic AR-15's. When it comes to function and reliability they're both going to be pretty even. So it's mostly going to come down to Wich one looks better to you. If it was me I'd go with the DDM4 v7 pro. Daniel defense is a great quality brand. Plus I prefer the feel of their grips and stocks. I'm not crazy about the bravo company buttstock and pistol grip that's on the PWS MK116 mod 2. So another vote for Daniel defense. Hope this helps and good luck with your choice.

Bruce, they are exceptionally close in build quality and functionality but, if I had a choice, I would wager toward the DDM4 v7 Pro. Cheers and stay safe!