In the last 10 years, I have owned and parted with three vacuums - Sharp, Hoover windtunnel w/ bag (best out of the three) and Hoover Windtunnel w/out bag (the WORST out of the three - it just fell apart and lost suction in the very short time that it took to vacuum my home.) I have bad allergies and a good vacuum is important to me.
In October, I finally agreed to having the Kirby people come and show me a vacuum and give me the two room shampoo/demonstration. My husband and I decided that the Kirby was the one for us (minus the shampooer - I have a shampooer, didn't need that feature). I did, however, need a longer hose to do all of my stairs. A Kirby vacuum is rather heavy (around 25 lbs. but it has two motors and is pretty sturdy. You also have to detach and attach certain accessories before you vacuum stairs. Seemed a little cumbersome at first but I got used to it.
The bags that it comes with are heavy-duty filtered bags made to limit the amount of allergens in your home. Upon the first vacuuming - I could tell it made a huge difference in seeing the dust (or lack of.... ) float through the air!
For the cost of the three vacuums, I could have had a Kirby. My neighbor just brought her Kirby in for a "tune up" and says that it works as good as the first day she bought it. Hers is 9 years old. I love it!!!!! I'm hoping it's the last vacuum that I ever have to buy. There is some wiggle room in the price and they always have financing options. They also have a "pay by cash/check option" for an additional percentage off. We took advantage of that. I'm hoping it's the last vacuum that I'll ever buy.
Good luck.
EDIT: The previous post said that, at the time, the Kirby was a hard sell. For me, it was "semi-hard". The man was a little put- out, at first, that he "had to shampoo both my rooms WITHOUT a firm commitment." This attitude almost lost him the sale. I told him that wasn't part of our agreement - I agreed to see his presentation, open-mindedly, in exchange for him shampooing my 2 rooms. He did back off and even suggested that he "leave the vacuum overnight" so that I could really get the feel for it. And.... yes.... that's when I fell in love! I thought the shampooing feature seemed like a lot of work.