We are in the market for a new dozer. Currently we have an old Case 450, 550E and a TD-15E. We are looking for something in the middle. Dozer will be multi-purpose, meaning, it will do everything from bulk push to fine grading. We own machines of several manufacturers so figuring it dealer support our 3 choices are a D5, Case 850 or a Komastu D-51. What are your thoughts and experiences ? :drinkup