Chasis will last just fine. These are from the 1980's, built pretty heavy. Even the drive train on these old toros are bullet proof, just have to grease and oil a few key locations. The one toro in the back ground I bought new in 1984, I've beat the living daylights out of it, its holding together fine.
I like this design as there is no lever to hold down to make it go, put in 1,2, or 3 and away it goes.
The weakest link is the babbit bronze bearing on the drive axle, but for the amount I will be using it it should be fine.