I bought a dirt devil when I first moved out, and it worked fine for about 8 months, and then it stopped sucking.
About a year ago I bought a hoover wind tunnel. And it's a heavy-ass thing that it looks like I shouldn't need it for my 1BR, but I do, and it's a lovely canister vac that sucks. It sucks when the canister is empty and when it's almost full. And it comes with three attachments that make my life easier. And, if I drop the fancy attachment, it's simply-enough designed that I, who has trouble with ikea furniture, can re-assemble it with no issue.
To a point, vacuums are as good as what you pay for 'em. Spending $40 on a vacuum will get you something that works for awhile, but not for good; find a good vacuum on sale for $120ish, and you're more likely to still be satisfied with your purchase a year down the road.
Spend $500, and you're wondering what else it will suck, because lord knows you've got nothing left in your wallet for it to swallow.