I am still waiting on my Kifaru hanging meat bag for delivery so I am not the expert on this but the way that I see it, because the material is weatherproof it is not breathable. This means that meat should only be stored in the kifaru bags for transport (kind of like garbage bags). Both garbage bags and the kifaru bags will leak slightly unless you seal the seams on the Kifaru. However, because the Kifaru hanging meat bag is designed to hang inside your bag and compresses I would say it is far better than the old garbage bag route. Most people like to hang their meat in the original style game bags overnight before putting them in a kifaru bag for haul out.