hi don
the 17 Castia's are great trailers. I do use a sway-bar with mine. the few times i have towed with out one i noticed a little sway in when 18 wheelers pass by. not bad but i have greater peace of mind with one.
the
casita has a 350 pound tongue
weight , you will see the rear end of the van sag some , how much depends on all the other stuff you have packed. this is where a
weight distribution hitch or air lifts for the rear of the van come in handy.