I was practically perfect in every way when I had a BMW - just as always!
In terms of people flashing you to warn you about stuff - In France its amazing! They will flash you from miles away! Everyone does it - and i mean EVERYONE! Last time i was there my dad got flashed, he said the police will be up the road. Drove on, no police, flashed again, still no police. This went on for miles! Eventually he pulled over to check the car, it was all ok. About FIVE miles up the road there were two police stood in a field chatting - blue jodphurs long leather boots and guns (i liked that bit). Now that's community spirit!