I own the 2C/35F version and this is my experience with using this quilt for 5 days in Killarney, Ontario a few weeks ago.
I'm really not sure why everyone keeps asking about the footbox. I found that when you tighten the bottom all the way, it keeps the heat in pretty well. In addition, the one night that I slept in windy and cold conditions (5C/40F), I just put my zipped up Helium II jacket over the bottom of the quilt (adding an additional layer around my feet) and my feet did not get cold that night. This way you keep the weight down and you have the flexibility to have your feet stick out the bottom when it's warm out. I think the current design provides the best of both worlds. I'll post a photo of the setup I used later today.
ktennessQuilts do not meet the design standards that traditional bags do, therefore they can NOT be EN tested. How did you (massdrop) manage to bypass what every other manufacturer cannot?
My concern is this is made by EE, which is known to exaggerate their temp ratings. When I've compared the down and baffles to other quilt manufacturers, they are sadly lacking. Obviously then, lacking in warmth. I would take a 20° for summer temps and nothing more. If it could be made wider, then maybe as an over-bag to extend temperature usage. Hope this helps people who are comparing for purchase. I wouldn't skimp on either the expense or quality of your insulating sleep system.