What a tough choice. I have many happy memories of the RAF Vulcan displays and the sheer noise and excitement it generated, but I've voted for the Concorde because if one is kept flying it might just be licenced to carry passengers and I just might get to fly in one.
One scared the living daylights out of me just after the Kegworth disaster when I was driving past LHR on a wet and foggy evening. I could hear this tremendous noise approaching and thought 'Oh no, not another plane in trouble' as it went over the top of the car. Then I saw the four afterburners lighting up the thick night sky, no sight of the aircraft just the four plumes of flame. A truly marvellous sight that has stayed with me ever since.
They should be given free to museums because they were given virtually free to BA, and the taxpayers should be able to see what they bought and loaned to BA for a few lucky people to pay to travel on.