I have seen quite a few in different places,particularly in Bournemouth,where whole families can be heard screeching away in some of the "Chines" (wooded valleys running down to the shore).There are quite a few in Oxon / Bucks as well ; one often sees them at night in the car headlights. On the whole,most of the ones I've seen have looked a bit mangey/scruffy/malnourished, as would be expected of any living thing existing on a diet of KFC -bones and regurgitated Donner Kebabs. I think that their natural place is in the woods & fields,chasing after rabbits,etc,and sometimes getting shot by irate sheep-farmers,but that's life.
          Eventually I suppose,somebody will die after being bitten by a diseased "urban" animal (Rabies,Tetanus,Weil's Disease or whatever),after which "something will be done " ----but not until then ! Meanwhile, IF I had a .243 Remington Magnum (virtually IMPOSSIBLE to do in this,the most over-regulated,anti-gun country in the world !) ----Well, I know what I'd do !! Humanely,of course.