I don't know anyone else that owns a NAH. I commute on the pike and I do ocassionally see another one. Priuses, on the other hand, are like ants at a picnic.

My wife drives a Passat wagon so that's the vehicle we use when we have to haul something but at about 10 mpg less than the NAH. I assume a roof box on a NAH would lower mpg but exactly how much is a question - probably not 10 mpg - maybe about 5mpg at highway speed??