I've had good luck bringing beer back from Europe using the smaller blue print tubes. They are just a hair larger than the guage of a bomber (22 oz) or 1/2 liter bottle. I cut them to fit the length of my checked luggage and tape up the ends with the existing endcaps. All you need is some bubble wrap or a sock to put in between the bottles. Just make sure there isn't too much movement end to end. No issues so far with temps in the cargo hold.