Up until now I have always used 21" HONDAS and They are in my opinion the best 21" on the Market. Now I am stuck between a 36" WB and a 36 " Great Dane SS. Both in the 15 HP RANGE. My question is how much fuel will one of these machines burn in an average day ? Example lets say Mower run time 6 hours ? Or If someone could give me a comparison maybe by Ratio ? I was guessing 2 to 2.5 as much fuel as a 21" ? Any input would me great. I figure now with a 21" I burn about 1 to 1.25 gallons a day on mower fuel ?