This film is difficult to watch - I'd say it was for hardened Frankie Howerd fans or lovers of early British cinema only. The plot is fine, Howerd's acting is great (you can see the talent bursting to escape) but the film is let down technically. It's on the Pickwick label so I never expected a visual masterpiece but even so the quality is really poor. My particular disc went into 3 second hibernation at 15 minutes, 30 minutes and 50 minutes. The worst, however, is at a reel-change where the viewer is treated to the 4,+,3,+,2,1, countdown.
Additionally, I think a section of bad frames have been chopped from the middle of the film. At one point, Frankie Howerd drops into a river having climbed down from the bus whilst it's on a bridge; but in the next scene, he's talking to his passengers behind the bus in a field.
I last saw the 'Runaway Bus' on television - the print had been cleaned and properly edited so what on earth were Pickwick thinking in releasing the film in this state?
Overall, the strength of Howerd's acting overcomes the poor presentation. This film is worth watching if you love him but worth missing if not.