You might consider the Ursack White model, with the metal enclosure. I've used it for several years with no problems in Sierra bear country. Problems with it have occurred when users don't follow the manufacturer's instructions. The closure knot has to be tied exactly as recommended, or bears can get into it.
But...check with the USFS and the Parks for their regulations. The Ursack is still not legal in SEKI and Yosemite.
Last edited by Bob West; 03/27/14 08:51 AM.