Depending on your overall design, using different colours/grout and limiting them (just kitchen or 1 bathroom) they will be en-vogue for years to come. But like all popular designs/products they have their time too. We're using the pattern just not black/white in our kitchen. I'm sure I'll be sick of them at some point years from now and have to update the kitchen - nothing new there!

Google glass subway tile and see if that's what you're after. Beaumonts have them.

Hi Emma. I'm not sure about shape of tile giving impression room is larger, but I do think large in either shape is the way to go. There are likely Houzz Stories which address this topic if you want to do a search. May I ask which pattern you have in mind for the subways? If there are other tile stores in your area, I urge you to visit them as the advice and helpfulness in the customer service can vary considerably.

Will you have an island? If so, is cabinet colour same (white) as other cabinets, or will it be a dark colour like in the pic? Is your window of similar size and shape, and will the kitchen get lots of natural lighting? I like the look in above pic. The black splash back looks good and this contrast of light and dark allows the window to be showcased. It works really well in this situation, especially as there are other dark elements in the room. If you want light to bounce off the tiles, gloss may be the way to go. May I ask what your bench top material and colour is?