Buddy does really well with his WizDog, though it's not the most fun when he has diarrhea
but I just pop it in the tub and spray it down and it's fine. Poopy's mom has it right - I spray it a bit with Natures Miracle and use a paper towel to wipe it off between cleanings.
One thing I found is great - once he or she is past the pad-ripping-up phase - I put the pad in the bottom of the tray of the WizDog and no more "missing" the pad (he has a tendency to pee on the very edges of any pad or the Wizdog)
Here is a cute photo of him when he was a brand new puppy and still kind of unclear on the concept ("hi mom, this is a great place to sit!")