I've only had two machines, neither new...one New Holland, one Cat. Both had tires. When looking at tracked machines, a friend who was a mechanic for years at NH, then DEERE, then NH again said, for our area, don't get tracks. We have extremely rocky soil. According to him, having replaced several of each brand (the NH store carried ASV as well), he had never seen a machine come in w/over 1,000 hrs on a set....and most often were replaced between 600 and 800hrs. I realize that in certain conditions, and with proper care, they may last much longer, but in my neck of the woods, that's not the norm. I trust the man who isn't selling me something.