I've had this Eureka Up 2-in-1 for nine months now, and it works GREAT!!!  I'm especially impressed with the fact that it gets the corners really well.  One thing they might improve is that it isn't balanced well, and keeps falling over (i.e., when changing batteries if you let go of it), but in the grand scheme of things, it's an excellent product.  I definitely recommend getting the 2-battery bonus.