It depends quite a bit on the color of the mat and the lines on it. My first mat was a Fiskar's, grey with orange markings. I find it very difficult to see the markings on that mat, so I seldom used it. I like the Olfa green mats, but I bought a couple of the US Art Supply mats (pink on one side, blue on the other) and I really like them better.
https://www.amazon.com/US-Art-Supply...9303&s=gateway