When stick vacuums were first released, they were meant for light-duty vacuuming tasks. House owners use it in between weekly cleaning sessions only, and they usually have a powerful canister or uprights for intensive cleanups.    These days, there are mid-range and high-end corded stick machines designed with powerful suction to your only vacuum. They can pick up ground-in dirt on carpets, tackle pet hair on upholstered surfaces. Still, some models are only suitable for quick touch ups or light cleaning, and they should be used as a secondary device only. So the essential tip here is to look at the specifications carefully before making the purchase decisions.