So, I am taking this trip next week, by car, and I am taking with me many sheets of 4X5 IR films. It's in the high 90's where I'm going, so I have concerns about the films spending much time at these temperatures. My plan is to put the film holders in individual ziplock bags with a silica packet, and suck the air out, then put all the ziplocks in a cooler with freezer packs. I should be able to refreeze the packs along the way, at motels or whatever. Seems to me that the real concern would be condensation, but it's pretty dry where I'm going, and the bags seem to hold a seal pretty well. Is this a sound plan? Interested to hear other considerations or tips from experience.