I picked up a Luna Pro SBC at a local camera store a couple weeks ago for $5. The guy said it was four stops off. I guess he didn't realize that the inner dial for the EV scale had been moved from its zero position. Put a fresh battery in it and it reads to within 1/3 stop of my Luna Pro F. Hehe. Then I turn around and spend $25 for a variable angle attachment for it on eBay. Fine with me. I didn't really need it, but I just couldn't let an SBC sit in that guy's junk bin for $5.