Re: F*ck every single flying peeping tom!
They're essentially illegal to fly outdoors in towns and cities.
The rules say you can't have a drone within 50m of people of buildings (excluding buildings "you control", I think the wording is, which is why drone racing can be legally done), nor can you fly it within 150m of crowds or built-up areas.
There's obviously a band between 150m up and the 400m cap, but how'd you get them there? You want to play with these toys, you need to aska farmer nicely or see if the National Trust will let you fly 'em (I expect they will in some of the less sensitive reserves, but I've not checked).