Just take him and you won't regret it! Easily one of the best math professors I've taken at UCLA. Also, keep in mind that he taught (and created) this course back in 2015(6?), so he is very clear and knowledgeable with the materials of the class. This class is quite statistics/probability heavy, so it's best if you ace your math 170E/A or stats 100A before taking it as your understandings of the lecture really depends on it.