Well, it will work fine for some types of locations. The biggest issue is thin walls between rooms. However, for underground locations, this typically is not an issue due to the weight bearing structure needing to be a bit thicker. Also, if you set them on a grid and have each wall be it's own tile, you can inset the beginning of the wall a bit inside the grid with the top being perhaps a tiny bit over the outside of the grid. Yes, you loose a bit of the interior, but it does make for a really nice dungeon.