Automatic pool cleaners can reduce pool cleaning time substantially by reducing the need to manually vacuum the pool.
Good pool cleaners can do an exceptional job of cleaning dirt and leaves from the pool floor and walls, almost eliminating the need to manually vacuum the pool.
Pool cleaners like the Baracuda will only move in one direction, so depending on your pol shape and things liek sharpness of corners, pool ladders and pool steps, teh cleaners can get stuck. That is where a cleaner like The Pool Cleaner has an advantage : they have an internal gearing mechanism inside that periodically reverses the direction of the pool cleaner, So it nevers stays stuck.
Polaris is a pressure side cleaner which means it is connected to a return jet. The water flow turns a turbine which moves the cleanera round the pool. A pressure side cleaner has a bag on top of the cleaner to catch leaves via a venturi action where water is pushed up through the debris bag.