I've been throwing around the idea of putting my canvas cutter on top of my cot. It has a comfortable 3-4 inch foam pad in it already. I've used it several times on the ground in weather down into the low 40's and it worked great with my current bag( 40 degree rated). I'm just not sure about the fit on the cot. It would give me a layer of canvas between the cot and foam pad then I could zip it completely up to hold in more heat if it gets extremely cold. I can also roll everything up in the canvas cutter for a easily transported sleeping kit. One friend that has been owns a furniture store and took a down twin sized mattress topper he put on his cot and said it worked great keeping the cold from coming up and keeping him warm. I'll definitely be getting at least one new bag rated -20 or -40 And a nice merino wool blanket. I'm going to try the canvas cutter on the cot this week at the house and see how it fits. Again thank you to everyone for there recommendations.