Thanks for humoring me Mart.
That makes a lot of sense, I guess in addition to diversifying your cooking methods one thing I hadn't thought of was the ability to make it yourself, or fix it if it breaks. Assuming you have some tinfoil or other reflective material on hand as a backup.
A solar lunch box is only as good as long as the dog doesn't knock it off the counter and the solar panels/batteries haven't degraded/died.
By the way, you mentioned a "Chinese parabolic cooker," would that effectively be the same thing, just a manufactured version from China?
When I get back to the states I'll try making one, I'm not a prepper but it seems like a fun project even if I won't get a ton of use out of it.
Although, maybe I become one, preparing for a rainy day is always smart. Even if it's not the end of the world, you can always lose your job...