Tommy, where I live it is very hilly, so it is impossible to keep the machine at a given throttle level given that it is a heavy machine (mine weighs 1735# full of fuel without me on it). With that stated, I have gotten 5-6 hours of use from a 5.3 gallon tank before. It was not totally empty at the time of refueling, but was quite close. My father's 825 I has done even a little better, but his property and usage areas are not as steep as mine and he putters around a lot more than do I. His machine also does not employ the brush guards, hydraulic lift for snow blade, full windshield, toolbox, and Fox shocks that mine does and weighs therefore around 200 pounds less than does mine. My opinion is that the Chery 3 cylinder engine burns about the same, if not slightly less, fuel than did the Kawasaki engine in my first XUV when running at low RPM under low loads. Having had both an XUV with a Kawasaki, a diesel, and the one I have now, the Kawasaki had to work hard to pull the machine and do its duties even at low ground speeds, but it did not seem to work (or be able to work) much harder when pushing the pace or under load. It also had a 3600 +/- 150 rev limit. My current 825 I will rev to over 5000 RPM's regularly and is encouraged to do so by the set up of the CVT. When pushing snow, pulling a heavy trailer or hauling a heavy load uphill, the machine wants to rev and that is when the fuel consumption goes way up. In my case, plowing snow last winter took about two gallons per hour, if not more in some cases. The 825 has much more power than does the 855d diesel, but it takes fuel to utilize it. One could probably keep consumption close to the lower horsepower Kawasaki engine (never close to the diesel) by feathering the 825 around or living somewhere flatter (like Louisiana), but in that case it likely would be just as good to get the 625i instead unless one just wants the speed.
John M