Tank tread

[Lil' Lavery]

I'm curious as to how the KoP drive failed last year. It is one of the most reliable drive-trains available, when properly constructed. It may not have the speed or flashiness of a shifting transmission, the agility of an omni-drive, or the contact area of treads, but it definitely works.
A properly constructed tread system is usually very reliable as well (but even the some of best teams have sometimes had trouble with belts snapping). That said, any issues that arise are often worse in belt drives than chain. For example, it's far harder to change the length of a belt than it is the length of a chain if the sprockets are positioned wrong, etc.
If you feel a tread drive is the best solution for your design, and you feel confident about building it, go ahead. But I just give you my cautions that they are no easier to build than the KoP drive system.