That's not exactly fair. To do a week of open circuit in a place like Truk lagoon, you could easily spend over a thousand dollars in helium. To put your unit on a plane is $100-$300 each way (depending on the airline). My unit travels as a carry on, so as long as I travel with US carriers into international places it travels for free. I would say that you need to travel frequently and honestly assess that you would otherwise be spending lots of money on gas in order to make the economics of it shake out - but the act of traveling with it is generally the cost of shipping a can of sorb ahead of you and ensuring that when you get there folks have the ability to do the fills you want to have done (though that last bit applies to open circuit even more).
