Another reason for not liking twins is also hard to prove ... the ratio of Toilets:Seats appears to be less favourable than on quads.
The difficulty is to travel the majors, count their seats and toilets and make up a table. I do not have the time and money to do so and Which? do not run reports on this sort of thing, only on overall punctuality.
However, when travelling on twins, the toilet queues SEEM longer.
[ 20 November 2001: Message edited by: PAXboy ]