Hi
I'm a fan of the pneumatic jockey wheel. Mainly due to its immunity to being stopped by small stones and surface irregularities particularly if you are moving the 'van around by hand.
All the solid jockey wheels I've had have not lasted as long as my pump up tyre.
I have had punctures but a bicycle tube repair kit soon fixes it.
Theory is the tyre acts like suspension, the tyre deforms over the surface rather than the solid wheel lifting the whole load when an obstacle is being negotiated. The energy to lift the 'van comes from the force moving it along i.e. you pushing or the motor mover.
The expensive Alko premium jockey wheel with built in nose weight gauge is even better at getting across rough surfaces as the gauge assembly acts like trailing arm suspension plus the pump up tyre.
A light caravan with low nose weight may not benefit from a pneumatic tyre but the average or above 'van would be much easier to push about.