I have an Olfa 24"X36" and a Martelli 30"X60". I like both of them for different reasons. But if I could only choose one I would choose the Martelli. I like the Martelli because it is big enough to lay out a lap size quilt and square it up easily after quilting. I don't usually have to move the quilt at all because the mat is long enough. I also like that I can flip over the mat if my blocks are near the same color as the mat. For example, I have a hard time seeing white on the yellow side, so I will just turn it over to the purple side. Likewise, it is hard to square up purple blocks on the purple side. If you are interested in the Martelli wait until the redline sale when you can get it 50% off.