I personally think that it depends on several factors: what stance the van has e.g. How low you go, what you are using the van for/practically and size of your bank balance.
My T5 had huge wheels and tyres and was lowered an impractical. It would cost me a grand a year in tyres due to wear and tear as it eat through tyres. Ride was awful but it looked ace! I ended up swapping back to steelies after five years. On my T6 she is lowered and I have Devonports and Goodyear Vector tyres. Drives superb, more practical and ride is great.