parabellum
You've been in Australia too long - next, it will be 'program' and not 'programme'.
LT, if you go BA you might get them the seats RIGHT down the back - there are tow rows, no third seat. Right next to the dunnies so they can muck up. Plus by the time everyone else has alighted they might see a pilot or two.
It would be at odds with my experience with BA or QF to think that their trip would be unpleasant. The UK Border Agency will make up for this, though. That's something no airline can fix.
SO