Far more cost effective and this is much easier to operate. My mom has a shark and that contraption broke within the first month! Not only that but it makes a lot more noise and has done more damage than good.
Honestly this is better than the Swiffer but I much prefer my Shark steamer. I think it's just the basic model (like $50 at Wal-Mart) and I will never go back to using the spray mops again. Go with the Shark!!
I like this better than Swiffer, because the pad is washable and it saves me a lot of money - plus, it's more eco-friendly. You can just put whatever cleaner you want to use in the container (Lysol, Mr. Clean, etc.)