I bought a new x729 aws 4x4, 4 years ago. This machine runs great the only issue I have had is replacing the mid center tie rod that controls the rear wheels and rubs up against the gear box on the mower deck. The tech said when I make a hard right hand turn that it causes to rub and pop the rod off the ball joint. Didn't know if any one else has had this problem. I have replaced the tie rod at a cost of (60 dollars parts only) four times since I had it new. Machine has just under 400 hours, other than that I have had no other concerns.