I run a DDM4v1 myself. It's a very well built rifle, and the included sights & rail are top quality. I really like the extended grip, and ability to mount a light in front of the front sight, that the 12" forearm offers. The anti-rotation QD studs built into the forearm combined with the QD stud receiver extension (buffer tube) end plate allow you set up almost any sling to your preferred configuration easily, right or left handed.