I have a MX5100 HST, 4WD, and have very different feelings about the HST compared to the gear drive. I have found for my uses that the HST is wonderful. It does use more fuel for power as it is necessary to operate at higher RPM's. However, for brush mowing on hills with trees it is unsurpassable for speed and ease of use. I have R4's on it as I cross ground (grass runway) to get where I am going and the ag tires cleat too badly. I have found this setup to provide adequate traction for my needs. I plan to purchase a lift disc harrow in the near future and have been shopping several brands including, Land Pride, Tufline, EA, and a few others. I would go with EA, but they don't know the weight of the harrows yet as they apparently weigh the unit when they make one for sale and the set that I am interested in they don't have a weight for it yet. Land Pride and Tufline are old, heavy, reliable brands, but they are very expensive. Most of my use is brush cutting, and loader related and the HST is far superior for that than geared models. My old Kubota was a shuttle shift and I loved it until I tried the HST models. I am shopping for harrows that exceed the width of my rear tire spread. A set in the 6-7' range.