Hi Terri,
I have the Shark steam mop and I think it is great. I have hard wood floors and it seemed that every time I cleaned my floors, I was leaving a layer of detergent on the floor. I used the steam mop and it was very difficult to push and the fabric piece was filthy. The next time I used it, it was much easier to clean, and the fabric wasn't as dirty.
I'm convinced that this is the best way to sanitize your floor (hot steam sanitizes and leaves NO residue) and it seems to be able to remove years of buildup the old detergents left behind. I got mine at Bed Bath and Beyond with a 20% off coupon. I saw it for sale at Costco but it was the same price as when I used the coupon. It comes with a second fabric piece and you can machine wash them (but not dry them or they'll shrink and not fit).
I love mine!
Liz