I've opened my pony many times for travel and look around but I don't have the training to know what I'm looking for. When I get to location I blast the inside of the pony with air from another tank (imho removes any humidity) and put the valve on immediately. Then I use my transfer whip to put a few hundred psi in it to keep it that way until I can get to the shop. It avoids any questions and costs for a new VIP every time I get off a plane.
If you’d like the knowledge, I’d recommend taking the SDI class. Much less expensive than the other one.