I have used TAG bags from Pristine Ventures in Alaska. They're tough, ultra-lightweight, nylon bags that are reusable and washable. I've been using them for about 4 years now, and have only thrown away two due to bones tearing holes in them. At around $50 for 5, I would recommend them for serious, lightweight,backpack hunting. If you're road hunting, just use the cheap ones, pillow cases, etc.