I do wonder how some people cope on trains, for hours without access to a drinkable water supply with BOB.

Personally, if I’m flying ET, I’ll Bring on Board or just BOB, certainly not interested in a portable water supply having seen what can grow in those things (accepting that it is usually in trace amounts with regular turn-over that is not a health risk, just not too appetising).

BOB discussions have been done to death on the forum so I won't reopen old wounds, but it certainly doesn’t stop me flying BA.