Spring 2017 - I took Math 33A with Andy in Spring 2017. I struggled with the material, but that's probably just a me thing. Andy was an okay professor. His lectures were a little dull, but he explained the material pretty well. He assigned a lot of homework. The midterms were fair, and the final was significantly more challenging. I'd take him over most other professors, but he's not the best professor out there.
Spring 2018 - Good professor in my opinion. Would have him again for another class. He was very helpful, nice, and approachable in office hours. The class was mostly very difficult because real analysis is a very rigorous topic. As far as individual professors for this course go, I have heard of there existing (lol, a quantifier. math joke) worse professors for this course such that they give unreasonable homeworks. His homeworks were very reasonable yet challenging given the nature of the course. His two midterms (I'm writing this before the final) were doable but not necessarily easy. The questions just weren't what I predicted based on the the homeworks and course material but the questions would absolutely fall under the category of what you would consider fair game (so just be sure to study comprehensively as opposed to focusing on certain topics). The average for my class on the first midterm was actually very high, but he explained this was atypical as it was not as high last time he taught the course (a.k.a., my particular class was probably just smarter). I would not necessarily suggest taking him for lower division courses however; he is a very intelligent professor and his math skills manifest in his lectures to the extent that lower division students likely cannot keep up with him. Anyway, I really liked the course. Not a bad idea to take Manion.