I have a large cutting mat ... grid lines are 57 X 29 with a 2" border on all sides (so 61 X 33). It's actually slightly too large for my cutting table, but not by much. Mine is the translucent plastic made by Beba. It is now 1.5 years old and as good as the day I brought it home, no rotary cutting grooves, no trapped fuzz in groves (because there are no groves!), no warping ... it's just perfect. I don't even wash it that often, but when I do it's just a quick wipe with a wet rag and it's done. Also ... my rotary cutting blades last a lot longer with this mat than they did with the soft green self healing mats.
http://www.bebasboutique.com/cutting-mats/