We arrived Th night quite late, in the driving rainstorm which might have contributed to the terrible boat accident on the Danube. We could have taken the bus, but the metro was closed. We signed up for the mini-bud van trip in.
The van trip was fine. What was NOT FINE was the wait. We waited at least one hour to get on a van. Once on, the trip was quick. But it was exceedingly annoying that there were 50-60 people waiting, and UNOCCUPIED VANS WERE SITTING ON THE PARKING.
So, it's convenient, it's quick, but if you come late and there are a lot of tourists on your plane, you may have an extended wait.