Thrush
you were complaining about tax in general

S1rst

our vans are fully refridgereated so they have the pumps going all the time, plus the extra wieght of the insulation etc and the drag of the cooler on the tops all adds up

with the vito's, driven frugrally and with the fridges turned off, you could just about get into the 60 mpg mark, driving the same with the fridge on would get you closer to the 35 mpg mark
with the fridge on and driving like a loon it was about 35 mpg and with the fridge on it was closer to the 22 mpg mark

and seeing as the fridges on the connects are not of the switch on/off able kind, there is no way to gauge how much better they would be

plus we have the high tops and even with the extra space that gives, the insulation takes up a hell of a lot of space, ther is twice as much in the vito and it's only another 18 inches longer and an inch shorter in overall hieght