Great!
These stones are great for both heat and cold.  I put them in the freezer for use when I get a headache or migraine.  The heated stones also work well for working muscles.  They can get almost too hot to touch, but do feel nice on the skin.  However, my one complaint is that they don't keep there temperature for very long.  You will only have a couple minutes of heat/cold before the stone returns to room temperature.
Rating: 4 stars