A friend had panels installed. Not sure of the brand. They are great in terms of cleaning. No grout means no mould. Just a squeegee to clean everything. Downside is they are plastic so can be dented and even cut by a screwdriver or drill while the accessories are being attached, but should be fine under normal use. You cannot use harsh abrasives and chemicals should be tested on a spare piece of panel before using on the shower.

Do you have photos of the room and the tiles?

My bathroom looks to be about forty years old, judging by the dated tiles. The tiles are awful, but the shower grout looks fine! If you like the small format tiles, I wouldn’t necessarily assume they can’t also go in the shower.

A shower with toilet floor 60 by 60 tile on floor and shower floor and a mix colour subway tile