I can't say about the ranchos, the bilsteins I installed last summer have been great. The only place I did not like the ride was on highways made of slabbed concrete when I was running 65. They seemed to "work" at a rate that allowed the truck to start a sort of harmonic sway. a slight speed change collared it in. Otherwise, they are much more comfortable than stockers and provided plenty of control while towing our 27' trailer.
One suggestion though, if you're planning for only a year before the lift, why not just get some napa or other part house stockers. Cheap and fit the need.