Rooter
Money List Winner
I use that section of the M25 very often and it will be fine Dave, it moves along ok as they regularly have speed restrictions which keeps it moving well, its only a few junctions around so its best imo to stick to the M40/M25.
With 70,000 people visiting Twickers, the scene will not fine im pretty sure. I would personally take Phils suggestion of the 404 and drop down to Bracknell. Or come off at oxford and drop right down to basingstoke and along the M3. You will probably be fine though, just have the option in your mind and keep the traffic reports on the radio and make a call when on the M40.