Compare to Montell UL Down Inner
I bought this to compare to the Montbell UL Down Inner. Patagonia does not post their fill weights so I asked the Patagonia rep. She said there is 2 oz of Down fill in this shirt. Now that I have the Patagonia and the Montbell Inner I can say there is NO comparison between the two! I don't know if the Patagonia rep lied or the tiny box stitching hampers the ability of the down to fluff up. The Montbell box stitching is twice as big as the Patagonia and this allows it to fluff up about 4 times the loft as the Patagonia (hopefully you can see this in the photo).
Things I liked: Simple design; less zippers to snag on the very fragile material.
Things I did not like: Way too THIN to provide much warmth. Price, even on sale it was much more than several Montbell options.
Montbell UL Down Inner
Things I liked: MUCH more down; fluffs up nicely; feels warmer. Excellent price and warranty.
Things I don't like: I don't like the pockets. The down is in the exterior portion of the jacket and the pocket is basically a piece of added material on the inside. This allows the pocket to pull open creating a small slit where there is no down. I intend to stitch the pocket closed so the pocket does not gap and cause a cold spot.