A little background: I am going to travel with my girlfriend in south america, starting in the beginning of April in Ushuaia, Argentina and ending in Lima, Peru 3 months later (passing through Chile). We plan to visit major cities and national park on the way. We will do some multiple days hikes. I expect to find temperature from 20 F to 80 F.
I need some help for the sleeping system. I always had sleeping bags, but I want to try something else, as I feel some claustrophobia in the bag. The ideal option seems to be a quilt. Problem is, I am not sure which one will fit the temperature range 20-80. I was looking at the katabatic chisos and palisade, or the Golite UL season 1 and the 3 seasons. I am afraid the palisade and the "Golite 3 seasons" might be too hot for when we move towards Lima. We will always sleep in a tent, so I guess it is safe to add +10 F to the outside temperature?
Finally, doing some research on the forums, I came up with a thread suggesting to use a nunatak back country blanket. I like the idea, although it looks quite pricey and I am afraid it will hardly ship to Europe in time.
I would greatly appreciate your suggestions!