My question was really aimed more at what to carry in situations when I *don't* think I'll need it ... but I'm wrong. What I might carry on a trip through the Nevada deserts is not the same as what I happen to have in the car on an ordinary visit to a friend's house a few miles in the country.

Space budgeting becomes an issue. I don't want to depend on something that has to come out of the car every time I need to fill the trunk with vacation luggage, shopping trip loot, etc!

And as I mentioned above I like the idea of smaller rations that can be spread around the car, just in case you can't get the trunk open after a crash.

It looks as though I should be able to get two day's food & water in the driver door's storage pockets, along with a PLB, CB radio, flashlight and escape tools: all within reach even if pinned in. Being able to get to the toy box in back almost becomes a bonus rather than a necessity in a lot of cases.

Both Datrex and Mainstay claim to meet some Coastguard standard. I hope to track that standard down at some point but I'm betting it means "lifeboat ration".