>>2472505I would say dont waste money on the liner. You could get a (free second hand) additional wool blanket, and cocoon burito wrap it and keep that wrap in place with big safety pins. If weight is the issue, take a look at the Defense 1 or XP TOP sleeping bags.
The problem in European autumn and winter temps between +4 and -12C is it's very wet, high humidity, and I have a lot of condensation on the outside of my sleeping bag in the morning. Down sleeping bags will be soaked after 2 or 3 nights. The fleece liner is just as fuzzy of a surface that will soak with moisture overnight if you use it as an outer bag in those autumn conditions. That's no problem if you are only out for one night, maybe two, but then it becomes a massive problem.
There are two ways to deal with this: Traditionally you could wrap a waxed and oiled canvas tarp around your woolblanket but its quiet heavy (1.5kg maybe) but the best way to deal with this is to have a extra synthetic insulation on the outside with a DWR coated nylon outside fabric - An outer bag like the XP Top or one of the Defense bags.
>>2472508Defense 4 is great. By itself the warmth experience can be very variable because its quiet a big almost rectangular bag and heat can easily escape. I would say freezing temps are no problem but if you want to get to -5C or max. -10C it helps if you are big too (fat not tall) or you have to wear lots of stuff, extra clothes around your chest and neck area to close the gaps.
The Defense bags are great as outer bags to stuff wool blankets, quilts, or just all of your clothes and gear inside.
