Well, I knew that the first Power-Up lunchbox was pretty flimsy, but I didn't expect it to be unusable by the second day. Matt undid both zipper pulls while he was closing the box after lunch, not too surprising given how tenuously the thing was sewn on. I knew that recycled zipper was going to be trouble.
So here's the new improved version. Not too pretty, but it's built like a tank. The sides are heavy denim backed with a stiff stabilizer, the interior is a thinnish silver vinyl (70% off from Joann's remnant bin- woot!) quilted with heavy batting for insulation, and the front panels were saved from the original. I'm glad I tried this, if only because I've never tried any heavy duty sewing on my cheap Singer and now I know the machine can handle much more than I thought it could. Buffalo leather toaster cozy, here I come!