A:Answer Hello Lana, this is Kelly with Dyson. Both the Ball Multi Floor and Ball Allergy Extra are UP13 models; they will perform in the same fashion and have the same suction power of 270 air watts. Both will feature a self-adjusting cleaner head which will automatically raise and lower to seal in suction power across all flooring types. The major difference between these models is going to be included tools. The Allergy Extra includes the carbon fiber soft dusting brush, mattress tool, reach under tool and the combo and stair tools. The Ball Multi Floor comes with the combination and stair tools. Since both of these machines feature ball technology, you likely will not fit the entire cleaner head underneath a bed that's 4" from the floor. We do carry many tools that can assist with cleaning under surfaces such as that. The flat out floor tool or articulating hard floor tool are both useful for reaching under areas like a bed. With the Ball Allergy, the reach under tool will be useful for that as well.
Best wishes,
Kelly
Dyson Customer Support
