My experience: extremely poor customer service and workmanship.
I used a deal voucher for cleaning and also paid for a light honing. The owner told me the honing would at least even out appearance/surface of my travertine floors, and I could always do more honing down the road.
The work spanned days instead of hours, and once complete, my travertine floors were left with ground-in swirls covering the entire surface.
I tried to work with the owner to resolve the issue.
Once I was finally able to make contact with the company, the owner and his helper came to my house to inspect the problem. The conversation became heated very quickly, and i felt extremely insulted and uncomfortable, and ended up telling them to just leave my house.
I have chalked this experience up to a loss and learned to do more homework in the future. I wish I had read all of the reviews, especially those that aren't visible at first glance, or at least checked Valleywide's standing with professional/business organizations/bureaus.