"And that's even when stored in an unheated garage. It's nice to use rechargeables but, honestly, with as long as an alkaline lasts in a taillight, it's just not worth the extra hassle."

I get several years of camping and touring out of one 2 AA cell headlight. I would like to have a dyno system, but didn't see the light till I had bought a bunch of other stuff already. Then there is the cost of all the bikepacks required to carry that stuff.

So how long with USBs be with us till we need to buy all this stuff over again.