Theatre tapes

Has anyone ever heard or owned the theatre tapes? For those who don't know what I mean, this is like an audiobook with a voice cast, music & sound effects. There is a Collins audio one and a Puffin one. I've had the Puffin one since I was a kid but never heard the Collins one.
Anyway, I recommend the Puffin one, I think it's closer to the book than the movie (as far as I can remember, I haven't read the book in years), beautiful music. Mr Hazel doesn't get very many lines at all though, though he is mentioned a lot throughout it. It's got Nigel Anthony as Danny's dad, Tom Saunter as Danny, Christian Rodska as the narrator.