Hmmm... I would expect that the collar would be worth it... especially when pushing to a 25-30 degree weather (Which we all know is within reason, given the superior nature of these two bags.)

I was just browsing online, I haven't seen them in person next to one another. I know that my WM Ultralite (59" shoulders) is plenty tight for me. Let's just say that it is efficient. LOL I wear a size 44 dress jacket, so that may give you an idea of my shoulder span and chest size. The extra 5 inches of shoulder span in these two models would be very noticeable and appreciated, as others have indicated. Sorry if my comment made you think that I went and looked/touched both of these models side by side. I didn't mean to mislead you there.

This is me giving my opinion when I know you haven't asked... the WM is lighter AND it has a collar. Those benefits out-do the 2 extra ounces of down in the FF bag, in my mind. The ONLY reason I would personally opt for the FF bag, is if I were concerned with the hip measurement and needed the extra 2-3" of room that the FF bag gives.