I have an 11.6oz, red, BPL 90 quilt, size regular.
I'm 5'9", 160lbs.
I find the cut of the quilt fine for sleeping on my back, or stomach. I find the quilt a little restrictive through the foot tube for curling up into a fetal position, I'd prefer the tube be 6-10 inches shorter. I mostly sleep on my side, and have generally had no problems getting full coverage with this quilt.
I pair my quilt with montbell thermawrap pants, and an REI spruce run jacket. I like to cook and hang around outside in the evenings, so I find this combination better for me than a heavier quilt. With this combination I've been comfortable in temperatures where the overnight minimum reaches the low 30Fs. I use a POE ether-thermo6 short pad, and foam from gossamer gear under my heels for insulation.
I would estimate that this quilt is designed for temperatures around 45-50F, perhaps using long underwear for the 40s. Below that you will want to think about adding in some insulated clothing to get comfortable sleep.