Solid. High quality. No nonsense.
Those would be the three descriptives that I'd attribute to Dukie's DSG. This won't be a full review as I've shot only a couple of hundred rounds through it, which is hardly enough experience and time on the shotgun to give it a fair write-up. But I'll express my first impressions.
The machining is superb. Dukie is a master. The weight is reassuring in its quality. It's balanced beautifully, being easy to handle, despite its solid mass and length. The matte anodizing looks tough, serious and industrial - all-business.
Assembly was pretty easy, especially after viewing Dukie's basic but effective videos from Page 1 of this thread. Listen to Dukie's advice and do NOT use an allen key on the three main screws (bolt and two pump screws).
I prefer a CAR stock so I bought an ATI. The plug fit was similar, but not identical, to the stock grip, so I needed about 9 minutes with a dremel tool to get a good fit (not a big deal). With the CAR stock, the DSG shoulders nicely and I can brace the pump action very well. The angle of the CAR stock goes up by a degree or so, but I also have an ATI spacer (about $10) that I might try that angles it down. However, there's no issues with sighting down the barrel anyway, while using my DYE i4 mask, so I may not bother with adjust the angle.
I used a CCM barrel from my S6. It's a temporary barrel for now as its beautiful finish looks out of place with the serious matte finish of the DSG. But the function is there - CCM's barrel sizers easily prevents ball roll out.
As with most quality-made closed bolt markers (which obviously a pump is), accuracy is excellent. The pump action is solid but not stiff. The trigger pull is predictable & smooth, without any binding.
I used it on a quiet weekday night at a local indoor field, so there hasn't been any input from other players, but no doubt, there will be a lot of attention on the DSG when I go to my next open game.
I'll leave it there for now, as I need more time to warrant further comments. At this stage, I can say that the DSG is one amazing, high quality, unique marker.