Alright- here are my experiences with driving in England in general and in London especially: the country roads had a lot of holes… it was - to say it nice- exciting
… though you have the feeling to crawl - but due to the holes you can’t go faster without risking to ruin your tires lol -
Driving in the city is like playing lottery
to get right in and out the roundabouts is for right side drivers really difficult- especially when the roundabout has 4 or 5 courses and the enlish driver seem to have no brakes - it was really really an exciting experience to drive there indeed- not to forget my several heartattacks as pedestrian 
and the parking spot costed a fortune 




just for fun, but not on long ways (it would cost to much gasoline) - When I’m driving ‘mormal’ I would say 50-120 km/h
but Germany is different - we have here in Germany “standard speed” of 130 km/h in our big 'Autobahnen" so you have to drive 100-130 with your car. If you’re to slow, you are the reason for an accident.