Ron - I bought the coin pattern tile and I think I prefer it a little over the diamond plate. I don't usually pull cars in wet in this garage but the condensor in my Lightning does drain water on the floor when I've been running it. Since I had to pull a rectangular section out so I can get my ERA in and out, it's not a big problem as the Lightning parks on top of the opening in the tile.
Kind of a bastardized flooring outcome but works for now. I don't have trouble with the tile moving - drop a 4-post lift on top of it and it won't go anywhere.
