Used this as trim inside my shower with the marbled pencil trim. I used Carrara porcelain tile. Don't be afraid of mixing materials. This is carrara with ceramic subway tile. The pencil helps deal with the possible thickness differences.
It's been so difficult to find an attractive one piece acrylic or fiberglass tub/shower enclosure. Love the storage in this unit! A one piece enclosure appeals to me after once having a bathroom where the shower and tub seam leaked.