I have a large Olfa mat that I bought in the mid 90's (white). I never use the markings on the mat anyways, so even though most of they have rubbed off I still use it. It is just the correct width for my table and I can't live without it. I have not noticed if my blades are duller with that over my self healing spinning mat. I would get a new mat just because I want one, but can't find one the same size so I will continue to use what I have. I have also seen the self healing mats that have been used at shops and the 1/2 yard line area has almost been cut through.
Good luck on your search.