I don’t think i would want my relatives to travel on a plane with something that resembles a very suspicious looking pipe in their luggage. Even a life straw sounds more efficient than this home made filter/pipe bomb.
If looks are important to you, suck it up and buy a straw. If something that has been proven for over a decade in the jungles of south america and can easily fabricated from simple materials is better, use the Colhane design. To me, functionality and being able to make something from scratch for cheap is more important than how something looks.
Also, the life straw isnt more efficient, because you still need to sterilize the water either chemically or with boiling to Ensure it is safe; Same with this filter. I have personally filtered and chemically sterilized 2 gallons of lepto rich water in less than an hour with the Colhane filter and a makeshift funnel attachment, so not sure where you are getting the idea that this filter is inefficient.
And being that Dave McIntyre travels to South America yearly with this filter, its highly unlikely it will be mistaken as a pipe bomb; especially if you exercise common sense and disassemble it before taking it on the plane.