I've used the Martelli and the Stripology. There's one marvelous thing about the Martelli -- it will not budge while you're cutting. This quality is offset by the fact that there is too much play in the slots and the cuts aren't accurate. I have trouble keeping the Stripology in place, even with the Guidelines 4 Quilting sticky strips on the bottom. So no satisfaction for me thus far, with slotted rulers.