I have hard wood floors and this mat has been a "temper" saver.  I had a rug to protect my floors before I found this and my chair would go off the side and it was horrible to try and move the chair around but I needed something to protect my floor.  I found this and it has been great.  It does not slide, it stays flat, if the chair goes off the edge it is really easy to get it back on.

Pros: Great floor protection for a hardwood floor