We are thinking of using slate tile in our kitchen, dining room, and utility room. We have looked at several options: Gauged vs. ungauged, multi colored vs. gray, 12 " vs. 18 ", etc. Anyone have any experience installing it? Is it tough to install the ungauged? How about using it in the kitchen. Is it prone to stain or any other problems? What is considered a reasonable price/sq. ft?