I've been using my cutting mat for 4 years now. I'd say I'm a pretty average user - lots of use on weekends and over vacation/holiday times (those times when I have a nice chunk of time to quilt my heart out). It seems okay, but then again, sometimes we don't realize how bad things can get (like how dull the rotary blade really is until it's changed or how bad our eyes are until we get new glasses, etc).
Any thoughts on this topic?