I have the smallest of the 20 series compact tractors the 1120. It now has over 4000 hours on it and mows a block that has around a 30-40 degree slope. It is hydrostatic, 4x4 and diff lock and will go anywhere! Time has come for some new oil rings, but thats not bad for 4000 hrs on an 18hp engine. Credit must go to Shibaura of Japan, the manufacturers of these machines.