i love my energy engine and tranny mounts, the car is alot more responsive and snappy feeling, but my old mounts were all torn the difference is alot bigger. i'd recommend the poly mounts. the solid ones, if your pushing over 400hp, will actually hurt the engine a little bit because it can't filter out the vibrations and shocks the engine, which can cause premature failure on some already weak spots on a stock HO 5.0.