The every 1/2 inch one is more useful, but more flimsy, as others have said. That flimsyness can make it dangerous. I was using mine when the plastic strips shifted and the cutter jumped out of the slot. Because I was putting weight on the ruler, I couldn't move my hand quickly enough and I lost a chunk of my left index finger. 0/10, do not recommend. (Losing a chunk of finger, that is. The ruler I'd rate at about 5/10, and I'm glad to hear that the Stripology is sturdier, as my JT one is about to be retired.)