MEC - Helium 250

I have mountain equipment helium 250 - packs small and pretty light. i combine with a cheap quilt (aliexpress) for very cold temps.

This is really one of those problems where the solution is spend a lot of money. Unfortunately.  I had a MEC bag that was fine, it was reasonably priced (around 300CAD on sale), packed to a reasonable size (it filled an 11L pannier), reasonably light (1.2 kg), and quite warm (-10C). No matter how I organized things this darn sleeping bag just took up too much space, and I wanted to get my base weight down to under 11kg - UL hiking background where you are often aiming for half that but bike bags and tools and parts are pretty heavy.  I ended up picking up a Rab mythic ultra something or other that was 600CAD heavily discounted.  It weighs half of what my old bag does, packs up the size of a melon, is almost as warm. Depending on where you ride weight and size matter a lot.