I just bought a '04 Exmark TTHP with the ECS which I'm pretty happy with so far. I have a problem with it when in reverse, you pull back on the hydro controls and the left side comes back at you much faster than the right. The tracking seems to be pretty good going forward though. I can take it to my dealer but, would just take care of it myself if it is a quick fix. Have any of you fella's had this problem?