Rating: 5 / 5
Please note: my comments pertain to the 2009 Primaloft One version of the DAS.
I have to agree that this is not an ultralight piece of gear. Not insofar as the insulation goes (the P-One is great stuff), but in the detailing. For me this is a bonus, for others, perhaps not.
The main zipper is a beefy #5 YKK. Having had quite a few main zips fail over the years, I appreciate this choice. I'll gladly take an bit more weight for long-term durability and ease of use. The draw cord elastic on the hem and the hood are also very thick (compared to my V.1 Houdini, for instance). An appropriate choice for a winter sports parka, IMO. The shell fabric isn't heavy, and lacks the superfluous shoulder and elbow reinforcements of previous versions. It is however heavier than current state of the art sub 1 oz/yard shell materials. All these choices add up. If Montbell made this parka, it would likely be closer to 20 oz for about the same warmth. I prefer the more durable construction. YMMV.
What is less up for debate are the quality of the design, construction, and insulation of the parka, all of which are superlative. The P-One is shockingly warmth for it's (lack of) loft. The insulation dries very fast, and soaks up little water. The DWR is high-quality, and the shell fabric also dries very fast. The cut is, for the size, roomy. Buy true to your normal size and all but the extremely barrel-chested should be able to layer anything short of a down coat underneath easily. The hood is roomy, but cinches down when needed, and the tail drops down to cover your butt. Not room for improvement here in my eyes.
The coat has two zippered handwarmer pockets and a zippered napolean pocket. All fine and dandy. It also has two massive mesh drying pockets inside the front on both sides. They seem a bit excessive to me, but you need not worry about having enough room for multiple pairs of gloves and socks, or anything else you care to stash away. If anything, it's problematic because you can overload the pockets with heavier stuff and resemble a lumpy santa in short order.
In summary, for winter pursuits like backcountry skiing (my primary use for this parka) Patagonia has things dialed. It's not at the cutting edge of ultralight, but may be ahead of the field w/r/t functionality over the long term.