I fully agree with 'oldish hippy' - holidays etc are all about relaxing so no need for speed.
I like the term Plodder - sums up the van well given that modern Merc vans are called 'Sprinter'
It's not the hare that wins the race lol
I was thinking about a small sticker for the back - "It's your hurry not mine!" Would surely annoy the odd sales rep