I've tried a couple folding shovels and I have to admit that for all the bolstering of being tough the blade actually bent quite quickly in even moderate snow and dirt.
If you're gonna get a shovel or axe you may want to consider the idea of a good polymer handle. Nothing against a good lacquered wood handle, but if it's going to spend most of it's time bolted to the roof rack that wood will probably dry out and start to weather over time. Last thing you want is the handle splintering from premature aging.
I would go with a good shovel you can really dig with, a good D- handle at the end might not be a bad idea. Basically if your in a situation where you really need to dig yourself out, you want to make sure you have a solid tool for the job.
Same with the axe, depending on what you're doing with it. If you're just using it for splitting wood at the camp site you may want a maul instead, but for just breaking branches and clearing some stuff a forestry axe might be a good idea.