There is a convoy of 9 minis I'm going up with to the motorshow, meeting on the A34/M4 services at Chieveley then again on the m40. The thread is
http://www.mini2.com/forum/showthread.php?t=56940
We could meet around Portsmouth early and then drive together up the A34 to the M40 and then meet up with everyone else. What you think! It would be great to go up in style all the way! The Chieveley services are about 1 hr away from Portsmouth.