You mentioned KY and moderate climates. Is the 20 degree just for CO and you have your normal gear sorted?
If not, one option is to layer 2 quilts or a quilt and a bag. It gives you more versatility. Ie. A 30 degree bag covered by a 40 degree quilt will get you to 20 degrees, bump that to a 30 degree quilt and you'll be roasting at 20 degrees. Then you have a bag to keep out drafts and a quilt for the warmer nights..
The system may be slightly bulkier then a 20 degree bag, but its divided, so easier to pack.
If not, one option is to layer 2 quilts or a quilt and a bag. It gives you more versatility. Ie. A 30 degree bag covered by a 40 degree quilt will get you to 20 degrees, bump that to a 30 degree quilt and you'll be roasting at 20 degrees. Then you have a bag to keep out drafts and a quilt for the warmer nights..
The system may be slightly bulkier then a 20 degree bag, but its divided, so easier to pack.