From factory cars have mostly rubber bushings to isolate NVH. Modified cars atleast in my 240 drifting world get either poly or aluminum bushings. I had Poly motor tranny steering rack and all subframe bushings replaced. Subframe got the aluminum's and the rest were all poly. That way the rear was as firmly planted as possible but I wanted some play with my motor trans and steering so I got poly.
http://www.4wd.com/Jeep-Lift-Kits-Je...n=DAYKU09017BK
Those are another good example. People use Polyurethane for EVERYTHING. These 3D printers can hopefully help lower costs