http://www.sewingemporium.com/
The link looks the same, but I got this one from Startpage (Google). You need to enable javascript. Think it could be one of the tracking apps that messed up.
I had a big mat. It did all right until I went to clean 505 off of it. The blue lines came off. I bought a Martelli at a show.
Larger mat (extra borders) for same size. Much thicker. I'm using a Truecut holder and either Olfa or Fiskers blades. Just bought some titanium, but haven't tried them yet.
Olfa does OK.