I haven't seen this one before. The typical problem you run into when hammocking in the cold is the air underneath you. It gets a lot colder than the ground does during the night. In a typical sleeping bag you crush the insulation underneath you which negates its usefulness. In the past I have just used a sleeping bag pad with a high r or insulation value. However, this looks like it might be a way around that. Anyways, hammocking in the cold can get kind of miserable. If you are using a hammock to keep your pack light I would recommend just sleeping on the ground when it starts getting colder.