I now own two backpacking sleeping quilts: a 18 ounce 3.0 inch loft down quilt (900-fill power with a 30-degree rating) and a 12 ounce 0.75 inch loft synthetic quilt (Polarguard insulation with a 50-degree rating). Each quilt has adjusting straps underneath, but no hood. Both quilts are mummy style with enclosed foot boxes. I bought these quilts in order to experiment with different light- and ultralight-weight sleeping systems for the backcountry.
I used my 30-degree down quilt by itself for a couple of years, but ultimately found it to be too much hassle keeping out the drafts when sleeping out in the open or under tarps. Main cause of the problem: I am a side sleeper and the width of my quilt was on the narrow side.
I now use my 30-degree down quilt as part of an integrated sleeping system. I layer my 30-degree down quilt over an ultralight summer weight sleeping bag (40 degree rating) and sleep on an insulating air mattress with a moderately high R-value (4.0+). This layered system will allow me to stay warm into at least the mid twenties. By replacing the 40-degree bag with a warmer 25-30 degree rated sleeping bag and supplementing both with an insulated parka and insulated pants will easily take me down into the single digits or lower. This quilt/sleeping bag/insulated clothing combination provides great flexibility over a wide temperature range. Sleeping in a standard, fully-enclosed tent (which I seldom do) would add even more flexibility.
I now use my 12-ounce synthetic quilt by itself when going fast and light and when nighttime temperatures are well above freezing (45 degrees plus). Sometimes I carry the synthetic quilt for emergency purposes on winter day trips. When nighttime temperatures are likely to be near freezing, I layer my synthetic quilt on top of a standard summer-weight sleeping bag.
Draftiness, when sleeping under the stars or under a tarp, is often a serious problem when using sleeping quilts by themselves. Being a side sleeper who shifts from side-to-side during the night further complicates this problem. I have mostly solved the draft problem by:
(1) placing the adjusting straps attached to the quilt underneath a fairly wide (25 inches) air mattress with raised side tubes
(2) wearing an insulated parka and insulated pants under the quilt
(3) sleeping inside a tent or bivy sack that can be buttoned up in stormy conditions.
One interesting side problem encountered using my 900-fill power down sleeping quilt with a bivy sack is that the bivy tended to compress the down when I was wearing all of my clothes to bed for warmth. The best solutions for this problem are to:
purchase a lower fill power rated quilt (say 650-800) or use a synthetic filled quilt that doesn’t easily compress,
purchase a larger girth bivy sack,
leave the bivy sack home when using the 900-fill down quilt.
Sleeping quilts are definitely for those who have patience and are willing to experiment. I experimented with many sleeping system components before I found one that works reasonably well. If I valued simplicity more than reducing my pack weight and if I didn’t like experimenting with gear options so much, I would have spent my backpacking bucks instead on a warmer down bag with a ¾ zipper (bags are available weighing only a few ounces more than my down quilt with a similar temperature rating) and called it good.
In conclusion, after much experimentation I am quite satisfied with using my two quilts to supplement my light summer-weight sleeping bags.