A 'campervan' or 'motorhome' registered in the same configuration as a Van with a Gross Vehicle Weight up to 3.5 Tonnes is permitted to travel at the same national speed limits as a car.
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But the same configuration of Van registered as a 'Commercial Vehicle' must travel 10mph less on single and dual carriageway roads with a national limit.
There is no reason for this when you consider both vehicles share the exact same chassis' and braking systems.
It is totally unjustified to apply different speed limits to the exact same vehicle due to their purpose.