Our van is a home from home, we use a matress topper, a fitted fleecy sheet and a duvet on the bed, never bought sleeping bags for us. I've never had a problem being cold or uncomfortable. I wanna go away!!!!!!!!!!!!
As duvets are so cheap in supermarkets I'd keep one just for going away, then there's time to air it before storing. Hate sleeping bags for anyone over 6 years old! mattress topper or opened-out sleeping bag on the bottom, fitted sheet on that, proper duvet and pillows. And a big fleece blanket in case it really gets cold. Don't put the duvet in a plastic bag as soon as you get up, it'll be damp(ish) from covering bodies all night! Try to avoid putting beds away at all, depends on space I suppose but takes SO much time.
you can build up your sleeping equipment according to preference once you've given different ideas a go over time. Ours is now,
2 sleeping mats, king size double height airbed, old opened out slepping bag on top,fitted sheet on top of that, king size double sleeping bag and a quilt on top. u can probably see the impression of our faces pressed against the roof it's so high. but it's fab and warm and makes my fella sleep properly !
I have found the best combo that works for me is to put a light weight duvet inside a double sleeping bag and then sleep under the duvet.
you get the best of both worlds the snug feeling of being able to pull the duvet around you head but the sleeping bag means that you don't get cold gaps at the edges and OH can't try and pinch it off me also the bottom layer of the sleeping bag provides extra insulation