Both models use the same tires with the same sizes for the drive and front wheels, so they will function in a similar manner. Nonetheless, the Z330R powered by a tougher engine and transmission will pull you through bumps and slopes much easier. It all depends on how bumpy or slippery your terrain truly is. Remember that skill is more important than the mower itself when you're mowing over slopes. So, you must be extremely careful to prevent any accidents from occurring.