I literally just got back from Duxford. (Our aircraft developed a tech problem so unfortunately we had to stay on Sunday, and could only depart noon-ish today.)
Very good show. Very professionally organized and despite the usual show business, the crew at EGSU were stars at trying to help us out with our tech problem.
Get a slot, fly in at slot time, read the briefing documents and you should have no problems whatsoever. Bear in mind though that departure after the show means that all of the pilots and crew of the 100+ private planes there need to be bussed over (using two small minivans) to their plane. It took over two hours to get all the people across and the planes away. If you do need to fly a considerable distance once the show is over (which was six-ish both days), make sure you get a priority boarding pass, and still allow at least an hour to get to the plane.
If you decide to stay overnight, make sure you don't leave your luggage in the plane. At 6 you are competing with all the crews wanting to go home, for a place on the minibus.
Also, when departing on Sunday morning, make sure you get a confirmation that you're allowed to. Today they decided at the last possible moment - no departures after 9am. We managed to get an exception made for us but I can sort of agree with their reasoning: the air at that point in time was already thick with arrivals. (As it transpired, the aircraft failed the runup checks so we had to stay for the Sunday show, get into a hotel again, and could only get an engineer to sort the engine out today.)