many manufacturers state that there tubbed stuff is suitable for use in dommestic bathroom/ shower areas so, i think you would be fine in most cases. I do not reccomend building up adhesive with tubbed gear though and would be cautious about tiling with tubbed gear for mosaics unless they are ceramic mosaics. My prefference would be a good powdered flexable adhesive. This is essential would for tiling to heavily use showers or wet rooms.
If ever you are incorporating a mosaic border you could perhaps consider using a decorative pencil bar/ trim above and belwo the borderwhere the border meets the tiles. This can be a nice feature to add and also helps reduce the visability of any flatness/ texture discrepancies between the border and tile.
I have heard people say my tiling is up and down like a dogs hind leg (and it is) but I have never heard of the dog tooth before so you learn something new every day
:8:
