Pete
Your dealer is correct they are like ice skates, even on wet ground, or some grassy conditions. You don't want to be sideways on a hill, thats for sure. The posssiblies could make a good movie

. I use mine at the end of my farm driveway where the snow gets piled up after a few storms. I have nowhere to push the snow off to, so eventually it blocks off the driveway. The excavator works great to break up the frozen snow/ice and allowing me to pile it higher.
When I purchased my first machine I had no idea of how start or run one and was nervous as could be. This was in the late fall just before the snow came. Once we had a few snow storms on the ground I found it to be a great way for practice. People probably thought I was crazy out in below freezing weather moving snow over there and back.You can move a lot of material and do no harm, but get lots of practice

For some reason I couldn't get the Rocky theme and sides of beef out of my mind
Last week I purchased a skid steer and have been out in the split hardwood pile picking up and moving wood around the yard: I wonder what the neigbours think

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As far as why I purchased the 91 over the 71 I will try to remember to the best of my abilty all of the facts. When I was looking at different machines I had it down to two manufacturers Bobcat and Kubota. The reason was, between them they have probably 90% of the market in our area and both of these manufacturers dealers have good service and a good name. The spec's for a 91 were comparable to a 331/430 Bobcat, with the 430 having higher ground speed as well as no overhang past the tracks. The Problem with the 430 was, it also was a little tippier(forwards and back) than the 91 and was a little wider to accomadate the o swing. Another factor was the Bobcat although comparable to the Kubota in most spec areas, was 40+ hp compared to the Kx91-3 with 28. Nobody at Bobcat could ever give me a good reason why I should have a larger motor that burns more fuel to do the same job. The big issue was the bucket breakout force, which for the 91 is 8053 over 6866 for the 331/430. In my experience this is a major factor, and more is better. Since time I have had mine boosted to approximittly 8900 with no negative results. This is not something to do unless you know your machines capabilities and are not foolish enough to do something that could potentionly cause harm to yourself or your machine. So how all this relates to the 91 over the 71 is; the 91 at that time was -3 and the 71 was -2. The Kx91-3 was the newest and biggest that I was able to haul legally with my one ton, in the Kubota line, and by getting the 91 you received the latest, greatest and most powerfull, IMO, that was available for me to pick from at that time. Did I make the right choice-who knows, but I will live with it.
Brian