Now that we have proven that 90% of the police forces in the UK can afford to run twins effectively, there will / can never be an argument to fly singles over built up areas.
How many hours do UK ASU fly a day/month? There are units in the US that have 24hr programs ( a helicopter in the air 24/7). Some smaller departments are able to fly 10hr per shift because they use single engine helicopters. This, they would never be able to do if they had to operate twins.