There's just me living in this space. In the 4mths I've lived here so far I haven't had to clean the tiles on back wall but it is dark so maybe I can't see the mess. As for the sink area there's water splashes always on the tiles. The kitchen designer advised me against using the mirror here for that reason.

Wall- use mirrors to reflect what you want to see, it will provide more light and hopefully the illusion of space. Can you put it on landscape orientation on the wall?

Hi, Neither is right or wrong. They just give a different look. If using a mirror I would choose the smoked. It looks classier and and I think it looks higher end/quality. It is also a softer version of the bottom colour and connects the upper and lower colours around the white. Cheers

Not a terrible idea at all. I placed two mirrors across each other in our small bathroom. The mirrors are not of the same width but are the same design and at the same height to maintain simplicity. One narrow mirror above the basin, same width as the basin and tall enough so that our tallest family member at 2m can see their face. The WC also sits next to the basin but I did not want to extend the mirror from the basin. The wall space above the WC allowed for decorative items, eg artwork; narrow display shelf to add interest and texture. Directly opposite the basin and WC is a wide cabinet, and a large mirror to cover that width of cabinet and at the same height as the basin mirror. This mirror also reflects the artwork above the WC. It reflects so much more light and creates a wonderful feeling of space.