I took Campbell for LS3 and I loved it. I completely understand how students are always looking for the easiest professor to take a class with, but you need to understand that this is UCLA and this is no joke. You are expected to perform. So stop wining and work hard. This class is doable, just make sure you know what he goes over. It is that simple. There are no tricks and he is very fair. Stop complaining and challenge yourself. I worked hard and got an A+. The only way the people above will say something nice about a professor like Campbell is if he was a joke. No, he was a great professor in that he challenged me, I learned A LOT, and I WON. Some people just don't want to work.
Dr. Lee was probably my favorite professor in the department. He is engaging, approachable, and knowledgeable. The class is definitely one of the hardest I've taken in the department, but I really found it interesting and rewarding. Tests are conceptual, rather than just memorizing facts. If I remember correctly, the second midterm and the final are open book. His class is only offered every two years, don't miss out when it comes around.