Should be OK, as long as it hasnt lost the rear silencer. If you have a CO monitor in your van, this may give you assurance that fumes are not getting into the van.
Obviously if it smells inside of exhaust fumes, its not a good idea.
Might also be an idea to check that where the exhaust now finishes, it isnt blowing on to something thats not heatproof (eg plastic water tank).
Dave.