Bests & Worsts Reviews from Amazon

I opened the box today and it's giving me an error code. It's asking to have the cliff sensors cleaned...but it's brand new! Cleaned them anyway with no success. I'll change the rating if it gets fixed. UPDATE: Shark has determined the unit is defective. They request I pay shipping $25!! I told them I would simply return it to Amazon for free. She asked a supervisor for a waiver so the new unit will be shipped free. I'm disappointed in Shark. We should not have to pay for shipping on a defective unit that's under warranty!!