Love, love, love Martelli mats. I have two big ones and, I swear, it seems like they sharpen my blades (also Martelli) as I cut. I know, it isn't so and I do have to rotate out blades but the difference is amazing. Get on their email list and they'll keep you posted with their big sales. They just had one and I bought two new rotary cutters and another mat.
I have the turntable and love that as well but don't like the markings on this one. Since I usually rely on the markings on whatever ruler I am using, that has seldom been a problem AND I can cut sitting down with this baby. I put this turntable one on my Amazon wish list and the kids got it for me! WOW! Makes me wonder who raised them! LOL!