Good question. I would like to here some disaster stories if anybody will share.
Recently I kegged an ESB, hit it with 25 psi for 2 min while I rocked it. I then let it sit in the keggerator overnight with 15 psi before driving 7 hours to FL. It was laying down disconnected in a cooler for the entire trip. Wasn't perfectly carbonated when we got there, but not bad. Very lucky in my opinion.
I'm about to drive 7 hours to Charlotte this week. This time I have two kegs chilled and being carbed prior to the drive. I have another keg that will go warm because it won't fit in the cooler. I feel pretty good about the kegs in the cooler, but don't know what will happen to the keg coming warm. Again, I gassed it with 25 psi for two min and set it aside, but it's never been cold to absorb the CO2. I will chill it as soon as I get there, and connect it to the CO2 while we're not drinking it (I only have 2 gas lines on my travel regulator).
So again, I would like to hear what's worked for others, because I'm still new to kegging. Especially, travel kegging.