Canisters vacuums normally have stronger suction than upright vacuums. Canisters can fill a dual role of a full-sized upright and a smaller machine (like a stick or handheld vac) for smaller jobs. Also the compact nature of these machines allows cleaning under furniture (usually a problem area for uprights).
Reviewers rate the “Hoover S3765 WindTunnel Bagless Canister Vacuum” highly for its ability to agitate dirt out of carpets. We like it because it is bagless, inexpensive (around $185-250), compact, and its HEPA filter can be removed and cleaned. With no bags or filters to replace, the vacuum is quite cost effective in the long term. On the negative side, some reviews found the vacuum noisy.
Available from Amazon for around $210.
The model previous to the 3765, the Hoover 3755, is available for about $170 from Amazon. The only features the 3755 lacks are the “Remote Fingertip Power ON/OFF Control” and the “Powered Hand Tool and Floor Brush Included”.
Product Home Page: Hoover S3765 WindTunnel Bagless Canister Vacuum