I made our 2-person Rayway quilt, Alpine upgrade with draft stopper and split-zip, in 2005 and we have been using it ever since. We are very happy with it. We've used it down to slightly below freezing without wearing much, and I expect it would go lower if we put some thicker clothes on. Around freezing we typically wear thin long johns, socks and a hat.
If I were to do it again I'd make it a bit wider since I toss and turn all night, causing drafts. I might make the draft stopper a bit wider too (we love the draft stopper!). We have no problem with storage space, perhaps our packs are larger than most (Golite Pinnacle and Golite Speed).
Since then I've made a number of quilts based roughly on the Rayway design, both one- and two-person, of varying thicknesses. One is a large but thin two-person overquilt (or summer quilt I suppose) that goes over the Rayway quilt and allows us to use it in much colder temperatures (coldest we used it was 15 degF and we were warm and toasty in long johns, socks and hats). We are happy with the Rayway footbox design, no problems at all.
Note: in ADK and similar leanto's place a ground cloth below you as drafts will rise up through cracks in the floor. We spent one night being cold no matter what we did until we realized this the next morning. No problems the following night using a ground cloth.