The MSport packages are very common over here, so not surprising you saw so many! Also, the Metropolitan Police (London police) use a whole bunch of different BMWs - predominantly though the 330d and 530d in both sedan and touring versions. Colours vary as well - white cars for normal vehicles, and in Central London red cars for rapid response vehicles and the armed cars.
Out in Essex, which is one of the home counties around London, they have a whole fleet of modded Subaru Imprezzas and Mitsubishi Evos as response vehicles. One of the other police forces in Warwickshire used to run a Lotus Esprit 300 as their highway pursuit vehicle!!
We're used to seeing high-end cars here in London - a Carrera GT or Zonda is not such a rare occurrence anymore
Bentleys are almost a dime a dozen, and Ferraris and Porsches don't even turn heads. Just in my apartment building car park, there are three 911 Turbos, three Astons (two DB9 and one V8 Roadster), a classic Ferrari Dino, Audi R8, a Bentley Flying Spur, and two SL55AMGs !!! My E92 is completely and utterly ordinary in that company (at least in the looks and ownership factor !!) I do have benefit from all these great cars being here - the security in the complex is fantastic!!