I like the DuPont sealers. They have a standard and an "Enhancing" sealer.....this brings out the colour of the grout and natural stone.

If you have a solid base on the tile below and there is no height issue there is absolutely no reason you can't tile over it. If the old tile has cracks, or if the floor shows any flex at all you should start fresh. Putting old on top of new is often done in many applications of home improvement. I just finished tiling over tile on my bathroom where the first layer was firmly tiled to my cement slab. It came out wonderful. My toilet flange happened to be elevated to the point that my second layer of tile is at a better level than the initial layer for seating the toilet. Picture is of this bathroom with the tile going in. The bathroom I did last summer had cracked tiles and appeared to flex a little, I took off all the old tile and the cement bed, added a layer of plywood to the subfloor and backerboard and retiled. Again, it just depends on what you are working with.

Yeah, I've drooled a lot over the Fireclay tiles. Definitely out of budget though. Daltile didn't have a whole lot for me. All the good tiles required an 8 week lead time.... I actually found a whole lot that I liked in the "Merola" line online at HomeDepot.com oddly enough. I thought I'd already looked at every tile in their online store, but I guess not. We'll see what they're like when they come in, but the nice thing about the big box stores is that it's easy to return what you don't use. Not sure how I would use it, but I have an urge to use this cool mosaic detail with a plain white subway. Kinda think my husband would object, though...

dgormish, I did use P&L Motif for my kitchen backsplash. I thought I had some earlier photos, but didn't find them. Here's a recent photo. The watercolor field tile, W78, is an almond color. It looks grayish in this picture because of the natural light this time of year in Los Angeles - "June gloom." P&L uses a different color chart for their Motif tiles than for their watercolors, so it took some effort to find a good color match between the field tile and the Motif. I had planned to include a liner between the Motif tiles and the framing tiles, but tile installer said I didn't need it. When he did the installation, he said something didn't quite line up and that he needed to add a liner. He asked if I had extra material from my countertop. So, the extra liner around the framing is Mont Blanc quartzite, from a remnant of my countertop.