So many people hate on him, but to be honest, Math 61 isn't the easiest class. Many people will struggle on this class regardless of if he was the professor or not, and I really enjoyed his exams. While his homework problems were by no means easy, it was simple enough to research and have TAs help you with them (granted, you put the effort into them). Keep in mind, I barely ever got 100% on my homework and consistently scored ~100% on my MT1, MT2, and Final. To be honest, his tests are extremely easy compared to the homework. Even on the first midterm, one of the easy homework problems even showed up as a exam problem, and as a result, I easily knew how to solve that one (this occurrence happened on all my tests, even the final). During the lecture, I will admit I understand how his class can be hard to understand. As a dedicated lecturer, he assumes you already know all of the preliminary knowledge (which is near impossible), making his classes harder to understand. What this means is that you need to do your own self study (crazy, right?). At some point, I stopped attending his lectures and chose to just watch Trev Tutor on youtube. He helped out so much and I learned a lot from his youtube videos. Oleg is one of those professors that you absolutely want to take if you have a big passion for math: He is extremely passionate and will share the same ideology with you. If you just want to have a class to pass: I would say, consider your skills in math. The homework will be tough, but the tests will be easy. This doesn't mean you can pass without studying. You still have to study consistently (just like any other class). Then, the class becomes trivial. Have fun with math 61 though. It introduces new concepts that will make many students struggle (a little like how Math 33A introduces new concepts in matrices: not necessarily harder, just different).

Besides the fact that he thinks everything is straightforward and fundamental, he is a good professor. His lectures are sometimes quite hard to follow but you can see that he actually care about whether or not you learn the material. Go to his office hour. He is SUPER PATIENT and will literally teach you until you understand the topic that you were confused about during his class. He is absolute nice person but not necessary a good lecturer...