One downside to using a steam mop (or any mop, really) is that you need to vacuum or sweep your floor prior to mopping. Some new combo machines are trying to shorten that process by combining a sweeper or vacuum with a steam mop, so you can do both in one step. There are only a handful on the market, including the Shark Vac-Then-Steam MV2010 (*Est. $130), the Bissell Steam&Sweep (*Est. $130), the Reliable Steamboy T2 and the Haan HD-60 Steam Sweeper (Est. $130). Of note, the Bissell Steam&Sweep, the Haan HD-60 and the Reliable Steamboy T2 do not have a vacuum component, but are instead sweepers combined with steam mops. There are limited user reviews at this time, and no side-by-side comparisons, but overall, the Bissell Steam&Sweep (that's how they spell it) receives the highest ratings from a significant number of people on user review sites, earning average ratings of 3 to 3.5 stars out of 5.
The biggest complaint of users of steam vacuums is that they don't vacuum or sweep very well, particularly around edges, and the dust collection cup is small. While the Bissell Steam&Sweep and the Haan HD-60 are both capable of steaming and sweeping or vacuuming at the same time, the Shark Vac-Then-Steam is capable of only one function at a time. To switch between vacuuming and mopping with the Shark Vac-Then-Steam, you have to attach a tray that holds the mop cover to the bottom of the vacuum. You also need to make sure you do all of your vacuuming first with the Vac-Then-Steam.
The Vac-Then-Steam requires you to wait 10 minutes after using the steam-mop function to allow condensation to clear before vacuuming again. No matter which steam vacuum or steam sweeper you are using, some users on Amazon.com and Target.com say that vacuuming or sweeping first and then steaming gives you better results. One major flaw in the Bissell Steam&Sweep is that the sweeper component is in front of the steam mop. Thus, it works well when pushed forward, but if you pull back owners say you are left with floors streaked with wet dirt. This design also prevents the steam pad from effectively cleaning the edges of the floor, users say.