I recently used my 20 degree 5 in 1 blanket on a hunting trip. We had night time temps varying from 25 to 40 degrees. Below 35 degrees, pending your level of self warmth, you may need to sleep in a medium, or heavy merino base layer. I stayed plenty warm with a light base layer bottom and med weight base layer top.
No actual pic of my puffle in the wild, but here is our camp.
The finish of the overall product is great..