I will suggest a set of tracks that I have first hand experience with. I'm not sure about cost, and in fact I doubt they are initially inexpensive, but they are, IMO less expensive in the long run. I can not comment on cost because I have not had to buy tracks thus far. To the point...I bought an '06 Bobcat 435 ZHS. It came with Bridgestones. To date there are over 2,500 hours on them. They appear to be a long way from needing replacement. Sure they have a few cuts and gouges, but nothing serious. Tread wear is minimal. We (myself and my employees) do not baby this machine. We do construction in terrain that often is very rocky, and on slopes (it is, after all, called the Rocky Mountains for a reason). Sufice it to say that I am impressed with the life of these tracks. I would be willing to pay more for a product that will outperform, outlast, or is superior to it's competitors products. It will pay off big time, in the end, with better up time and extended service life.
Food for thought.