I was offered it but as a keen amateur detailer prefer to do it myself.
If I were to entertain the idea of someone laying down some protection on the car I'd get a professional deatailer in to work his magic. Just don't trust dealers when it comes to cleaning - I even specifically request my cars aren't valeted when in for servicing.
Is autoglym not worth considering either? I was in fact thinking of getting that done. Having second thoughts now. How comfortable would a dealer be with a third party coming in to do the detailing at his premises. Anybody done that?