Not sure I'd ever not take a bottom quilt personally. If it looks to be warmer, I'll take a 30 degree. In the unlikely case (this time of year) that's too warm, I'll just loosen the ends to let air move through it. Too small and too light not to pack along in case things get chilly.
“I would rather sit on a pumpkin, and have it all to myself, than be crowded on a velvet cushion.” - Henry David Thoreau