You can work surprisingly steep ground with one,30 to 35% grade. The trick is you have to fell down the hill,this puts all the weight on the drive tires and you can use the saw head to counter-balance the back end. When I worked mine on soft ground I used dual tires,24.5-32 on the inside and 18.4-34 on the outside,this way when I did work harder ground only the inside tires touched,reducing wear on the driveline. However, if I was looking to buy one now and the terrain that I was on was a mix of hilly ground and lowlands,I would go with a tracked one because you can fell up a steep hill with it. Also, tracks have less psi of ground pressure than a wheeled one,even with dual tires.