There's been a bit of discussion on here about that exact topic recently. My personal opinion (having owned a VFII CalaisV wagon) is that there is far too little room, and the roofline is far too sloping to comfortably fit a dickie seat in there. It's not like the old wagons up to VZ (or God forbid the ginormous Falcon wagons). If those extra two seats are going to be regularly used it's going to be a real punish for the poor occupants.