The hydraulics on my old mower operates just as smoothly as my new system, the only difference will be the industrial HyperDrive will hold up much longer than the old system. I have been on a couple of friends Super Z mowers that are the same as mine (2006 yr. model), and they operate no where close in smoothness compared to mine. One was so different I believe the hydraulics were in the process of failing, but I was not about to tell him what the repair would cost. When I felt my hydraulics changing; the pumps and wheel motors were replaced, I did not run the mower once I knew the failure was imminent. If you operated my mower, it would feel like the mower you owned with the XR-7 deck when you bought it new and ran it the first day. What year model was that mower, and which engine did it have, I think it was two mowers back from the one you now own?