We purchased this unit with all of the goodies (shampooer, etc.) in 2000 and we still have it and use it. The built in auto drive is a MUST due to the weight of the unit. Cleans well - the shampooer leaves a bit to be desired however. Maneuverability Heavy and hard to turn. Ease of Maintenance Only a belt and a bag to replace - very simple maintenance. Suction Performance Will suck a golf ball through a garden hose! EXCELLENT suction power. Versatility Versatility are you kidding me? This is the transformer of vacuums I even blow my driveway off with the attachments! Design Exceptionally designed and built like a tank - weighs about as much as one too! Durability We bought this unit 14 years ago and still use it when we need to do a whole house vacuuming or to shampoo larger areas than our spot bot can handle.