Dyson DC 07
The Dyson DC07 is often considered the "original" dyson vacuum. It was the first of the series to claim no loss in suction for the life of the vacuum, and it is still one of the best selling Dyson vacuums today.
This is a very powerful vacuum. This Dyson model is great on pretty much any floor surface except maybe an area rug, as its power tends to try to eat up the rug. The suction power is unquestionable and you will never look at a friend's carpet the same after vacuuming your carpet with the Dyson DC 07.
Some of the pros of the Dyson 07 are the powerful suction and the quiet operation. The removable canister is also very easy to clean. It also has a very long hose and is easy to clean crevices and window sills. The bagless design is great for the environment and also helps save money in the long run.
A few of the minor cons of this vacuum are that it is a bit pricey but you should be able to find a good deal after searching around on this site. As mentioned before it is also a little rough on area rugs and takes some time to assemble, unless you find one that is already put together.
If you have hardwood floor or wall to wall carpeting, then you can't go wrong with this vacuum. If you are looking for a vacuum with good design and power, then take a look at the Dyson DC 07.