This site has answered so many questions for me over the last 18 months or so. Finally I have something to say, so here goes:
I have used the Outsak, Animal Resistant Storage Bag on 2 occasions in the past 6 weeks. I have a habit of using established sites when I backpack. Nice for environ, but not so nice on campsite critters(easy pickings for them). 4 months ago I did a trip where I hung my food and some animal jumped from the tree, or limb, or climbed down the line to get my hung food. A friend did a trip to Grand Canyon and came across this bag at a store on the south rim.(general Store I think). He told me about it, I ordered one from the manufacturer at www.simpleoutdoorstore.com and I have used it on two outings. The second of which an animal of some sort got to our hung Outsak and pulled on the wires a bit, but got no food. This things works. I guess it helps when the guy down the trail didn't take any precautions, other than hanging, to keep the critters away. He had a heap of junk to clean up in his site.
I recommend the Outsak to everyone I know who backpacks. This is a great bag made of steel wire mesh. The top closes with velcro, thick velcro, heavy duty stuff. The wire is enough to keep out most critters. There are some warnings about bears and ravens.