I had Quadvan install this when they did my conversion so I can't speak to what the difference running without the stabilizers might be. The Amazon.com link to the product that Roonie installed (
http://www.amazon.com/gp/product/B001QI4754) doesn't look like what I have or what is pictured in his photo, so maybe we are talking about something different.
If you compare the Quadvan kit to something like this (
http://www.suspensionconnection.com/cgi ... 66250.html), the reason Quadvan's costs more is apparent. Quadvan's mount is powdercoated heavy-duty steel and the shocks are Bilstein. Hard to say if that justifies spending $495.
I am running with 275/70R18 Nitto Terra Grappler tires and my van tracks straight and handles beautifully. Unless I uninstall the stabilizers, I won't know if they have anything to do with that but I won't be doing that anytime soon.
Steve in L.A.