We're at that point in building where I'm considering tile brands and colors. We're going to tile our showers and would like this tile to match the floor tile. Problem is I've found a good sale on travertine porcelain tile that I'd like to take advantage of but the wall tile isn't available. If I were to buy wall tile separately and match it to the floor, what are the differing qualities between wall and floor tile that I need to be aware of? And is there a wall tile for showers that isn't glossy (slippery)?