Go with the heaviest weight you can find. You won't have a problem with the pleats, and any wrinkles will fall out overnight. I have one lighter weight box (13oz), and it requires more pressing, and careful sitting in the car, to look neat. The other "boxes" I own are 16oz+, and they are easy to car for, and travel very well. In fact, my Matt Newsome is my favorite road trip kilt.