I too went with the Thule fake rain gutter system and often carry two glass
sea kayaks.  Can't pop the top without them off but I've seen it done with
whitewater boats on top.  Does anyone know what kind of loads those struts
can take?  

I also  plan to spring for the Thule super high feet which will fit in the
rain gutter over the luggage top not the pop top for when I only carry bikes.
 With the thule fork mount system I should still be able to till pop the top
with the bikes on.  The height is no big deal.  Jump on the wheel well and
grab the bike.

The down side to carrying bikes on the back is that some day someone will hit
you or you'll back into something.  Been there, done that.  I think
 expensive sporting equipment belongs on the roof or on the trail.   Wwatch
the drive-in windows and the garage