It's 24 hrs (give or take) from getting the boxes out of the freezer storage on the peninsula to getting them back in the freezer here at home in MN. In the past, the waxed cardboard boxes (with no extra insulation or gel packs) have done a pretty good job, with just a little edge thawing, but nothing too much. This trip I got the styrofoam lined boxes from 2 packers, and figured they'd be at least as good as the others. Not quite... of the 3 boxes I brought home, on 2 of them the styrofoam had broken, no doubt from rough airline handling, and there was more thawing than in the past. Still not all that bad, and I was thawing the majority of it right away anyway for the canner, but it did get me thinking...The old waxed cardboard did a good job, could I line them with something to add just a bit more insulation? I don't really want to add gel packs, less fish weight then obviously. What about some kind of insulating wrap? So far I've found 3/16 inch thick foil lined bubble wrap...flexible, cheap enough...any thoughts? Not sure if it would be reusable or disposable, but it's cheap enough so I don't care. I thought about lining the boxes with foil, or maybe those cheap "survival space blankets" neither of which do anything more than reflect back the temp of the product, but maybe that would be enough. Thoughts?