transits are a bit weak round the clutch area with their dual mass flywheels, and at £550 a time expensive.vauxhall/renault have trouble with gearboxes on the vivaros and engine problems on the movano's, but they are supposed to be getting it sorted. Ducato/relay/boxer's are ok but they are having teething problems with coolant pipes across the engine bay, blowing fairly regularly.
your van maybe sluggish, and the swb transit with the stripe might be quick and look good but how fast do yo want to go with a full tank of water slopping about in the back making your van unstable??