In reply to markryle:
Hi Mark. Nice pitch there, and glorious light.
Yes, I have a sleeping bag, a Thermarest Hyperion 32. Not really a winter bag on its own but it works with the down suit to deliver a cosy winter experience. I know it sounds implausible getting all that, plus stove, pot and food, into a bumbag but it can be done.
I've since transitioned to a race-vest-based setup, which is even lighter: I can get a winter baseweight down to 3kg.
https://lighterpack.com/r/tyhuph