Used McDonald’s Derivative Markets to study for a professional exam and used Hull’s book for a class and will be using it for another professional exam.
McDonald’s Derivative Markets is easier to understand for people with a less quantitative background. It’s the required book for derivative classes in Northwestern Kellog’s MBA program where McDonald teaches.
Hull’s book goes into greater depth, but at the same time will be more quantitatively demanding, especially the topics at the end. Like others said, Hull’s the traders’ bible.