Very few vaporizer designs can be cleaned 100%. The only one I can think of would be the types which are 100% glass on glass, such as the Vapocane. You would still need a 18.8mm glass on glass piece on arrival, or maybe just bore it into an apple and try not to melt off your face. Box vapes, mflb, supreme, VGs, - all would be dangerous to take on a plane.
But yeah, vapocane could be cleaned 100% legal in 3 minutes time. Never really pondered that as an advantage of the design. Empty your jet lighter and check that too and you're set.