my father in law has these trees. he used to trim them himself. 3 years ago he nearly lost his arm in an accident. They are now gone.
I have some in my front garden but have kept them about 8 foot high, like a hedge. Once the kids are a bit older I will remove.... they like to climb in them at the moment.
When I was growing up the football aways went into to neighbours leylandii. The smell and the cobwebs and the crap and insects in the hair and clothes.
I could scream.
Where do you live? They're illegal in some county council areas.