Small Tile or Big Tile

[Evan Larkin]

I am currently constructing a Quadraplex rental unit to keep for the long term. I am trying to decide between  3 x 6 inch subway tile and 12 x 24  inch tile for the showers. I like the look of the subway better but I fear the all grout lines will be difficult to keep nice over time. Anyone have any advice or rules for tile size in rental units. Thanks