Innovation is obvious in the Sierra Designs Cloud 800 / 35. This is especially appreciated for people who are looking for the most attractive features of a sleeping bag, coupled with the philosophies of a quilt. The Cloud 800 pairs a generous sleeping hood, deep footbox, and the cut of a mummy bag with a quilt-like zipperless design that's easy to get in and out of, as well as adjust and vent. The bag's approach to comfort and versatility works best for back sleepers. If you're a side or active sleeper, perhaps look at other products. All the design features take a lot of material to stitch up, which makes this bag's warmth to weight ratio lower than most other bags in our review. The zipperless comforter design affords a ton of room for those with wide shoulders, which separates this bag from models we've tested with a slimmer design in the chest to reduce weight.