I went skidding down a compound hill into my neighbor's tall grass the first time I took the Ryobi down the hill to the "blueberry" patch. It slopes only slightly but slopes to the side as well towards the neighbor's. Then I went looking for videos on how to run them on slopes. Carefully. Slopes with ponds or fences at the bottom are best done by backing down to the bottom. Some can mow across the slope, but compound slopes can be a problem.
My first time around some of my fence surrounds around some small shrubs and trees resulted in one of the rear tires smashing the fence.
Main reason I got it is to enable ME to do the yard in front and to both rear sides of the house. Will do this, but the left rear is a challenge, as it has a slope that I'll have to back down and go up. The thing is a billy goat going uphill because the weight of my body ends up pretty much concentration right onto the tires. The wife had normally been doing the yard with a self-propelled push mower, but she cannot do it in the high heat.