One of my tilers has just completed a wetroom using the new Stratum tiles from Topps Tiles. The effect created by these textured porcelain tiles is stunning. They come in a large format – 300 X 600mm but give the look of a stone mosaic.
You do need an experienced tiler to install these and even then it can be tricky. The greatest challenge is the grouting – because of the surface of the tile. The tiles are so rough the grout gets stuck on the face of the tile as you try to wash it off. In the end we had to use a grout remover on the tiles to get them clean.
I would suggest using a pointing/grouting gun on these and minimising excess grout as much as possible. Then go over it dry and remove excess before washing the joints carefully with a damp sponge.