>>2225604It is super comfortable. Just make absolutely sure it is closed tight.
It will not keep you warm 6-8 hours. Rather 2-3.
But the water will keep body temp all through the night, so you have warm water to make coffee (body warm water boils much faster than close to ice) or breakfast or brush your teeth. That alone is worth it.
Like other mentioned a winter pad (insulated air or thick foam) and either a new bag or a second one is the foundation for autumn/winter camping.
I use my 11°C / 52F (down) summer bag to -5°C / 23F by adding a thin liner an old fleece blanked and a quilt blanked (down). Sounds unnecessary complicated but weighs the same as my winter bag but is a bit warmer, way more compact and I can choose exactly what I need for the given temp.
