Flooring Tile - Wet Saw Questions for cutting slate tile

I need to cut 16" pieces of slate tile (about 1/2" thick) for use on a fireplace hearth and surround. The wet saw for rent at HD has a deck of 12", which means I'd have to support the 16" piece partly by hand and very carefully so it doesn't break as I pushed it through the blade. The guy at the rental desk was recommending this little handheld wet saw to purchase as an alternative. He said you could take two pieces of ply and lay them on the ground with a gap in between, then put the tile on top and run the portable wet saw over it, using a 2x4 or the like as a guide. It pulls water from a garden hose (I think) to wet it down. Does anyone have any experience with one of these handheld wetsaws? Should I just go with the rental and be careful not to break the tile?

Are there any other rental places you can go to? If you can get your hands on a Target or Felker for a day you will have no problem cutting those tile.