Pete,
I always travel by train to Duxford and go through from Ipswich. The journey is a pleasant one, much better than going by car and helps to relax more.
When I get to cambridge i get the courtesy bus to the show which is one of the most thoughtful ideas that the show organisers have come up with.
Sorry if my post was over bearing earlier but it has just become such an annoyance over the years when people start to pick apart these shows.
NS