Liking the Carrara marble look, I generally go for porcelain tiles for easiest care. Good quality tiles look "true" enough for using real marble details (as in on the edge of a bench and countertop across the room. This is what I have in my own bathroom. We keep a squeegee in the (large) shower and routinely clear water off the bench and into the drain, effectively drying the floor. Water contains minerals and ANY surface may show effect if it is left to pool. Stone can be sealed and grout must be--but note that in some jurisdictions, grout is NOT typically sealed as part of the job.