I installed Poly Isolators a few years ago. Still like new after around 40K.
Measured ride height before disassembly, it was at tha bottom of spec. Poly restored to slightly above mid spec. Car went up about 5/8 "
At the time there were no alternatives other than OEM that are junk that squish out after a few years. Aftermarket look better than OEM, Poly will last forever. http://www.dodgeintrepid.net/showthread.php?t=127998&highlight=poly+isolators
Also, if you don't feel like spending the money on poly, Monroe makes rubber iso's that are much cheaper, but far better than the foam crap they originally put on. IIRC they're less than 10 bucks a piece on Rock Auto.