"In part, the question relates to your resupply plan — i.e., Kearsarge pass or not, climbing Whiteney or not, MTR vs. VVR, etc."
To extend this from Brian's post, I would say that before you acquire a bear canister, you need to know how much volume you need in a bear canister, and that is generally a function of how many days you will be out between resupply points, such as the long piece from around Mount Whitney up to MTR. If you say that is going to be ten days, then that means something. If you say that is going to be only three days, then that means something totally different. If you know that you can eat OK on 100 cubic inches of packed food, then that means something. If you don't know how much volume your packed food is, then that is a problem.
For short trips, I use a Bear Boxer or else a Bear Vault 450. For longer trips, I use a Bear Vault 500. You never want to have to carry more than one at a time, although it might be possible to switch between different ones during a trip by use of a bounce box.
–B.G.–

