Hmm...this bag at first glance looks like an ultralight 20 degree bag yet...at around 40 ounces it looks to be more like car camping gear. The tight fitting cut w/elastic seems a great feature yet I still doubt this would be the 3 season bag it is striving to be. It is an interesting effort yet does not fit into my weight-weenie aspirations. It may well be worth the MassDrop price though!