Hello there. Looking at the Carinthia line of sleeping bags. Seen a model called the Explorer Top MF used by Danish Forces. It is a summer bag available in XL size. To me it looks a lot like the Defence 1 bag. Weather resistant outer covering with the Gloft synthetic filling. Would like to know if this bag could he used in the summer as designed and then also be used with an inner bag for colder winter use? I have the MSS Patrol bag that is also mummy shaped and could be used as an inner bag. Thank you.