London deployed 2000 police, and spent a paltry £1 million to support the Chinese propaganda rally (or Olympic Torch Relay, as they would have it). We had 35 arrested, and the flame stayed alight at all times. The French, in comparison, deployed up to 3000 police; no idea what this cost, but they included 65 motorbikers, 200 roller bladers and 200 riot police.
Only 18 demonstrators were arrested but the flame was extinguished no less than four times, had to be taken to a place of safety (a bus) and the ceremony at the Hôtel de Ville was cancelled. I'd say that's one up to France.