Professor Visan tells you at the beginning of the year that her tests are just as difficult as her homeworks. Take this advice strongly and do your homeworks and you will do well in the class. I redid homework problems (including textbook problems) before each midterm and the final and got an A. Simple class.
Fall 2018 - Visan is a fantastic professor! I took Math 131AH and BH with her and she is my favorite professor at UCLA. THE BEST, period. Her teaching is so clear, and she writes everything on the board, so even if you don't understand it right away in class (analysis is hard, and honors class is no joke), you can totally go back and review your notes and you will be able to understand it (of course you should be willing to put in effort to this class). She has beautiful handwriting by the way. Visan has a fantastic memory -- she lectures without notes, and never makes a mistake -- and she takes the effort to memorize every student's name (she will know how everybody is doing, so don't shirk and expect an easy A). She is extremely kind, patient, and encouraging during the office hours. Her homework is not easy but is carefully chosen to help us really master the material. They are relevant to what is taught in class and is very good for preparing the exam. Her exam is fair and reflects the material taught in class and the homework. Going over the exercises in Rudin really helps. Often there will be a problem from the homework and a problem from Rudin on the exams (they are the giveaway points). The best thing I like about Visan is that her wording is very clear, never ambiguous. Unlike other professors, you will never be confused about theorems or problems due to ambiguous or careless wording. This makes studying so much smoother. She is quite generous about letter grades. If I am not mistaken, the median grade is about A-/B+ (of course as an honors class, many people drop the class midway because the material is hard and whoever persists are generally capable of mastering the material). Just as a final word, the above is for pure/applied math majors intending for graduate studies. Professor Visan really prepares you for the basic exam. Take her class, and she will train you to be a mathematical analyst. If you are not a math major or not interested in "pure" math, Visan's class might be a little bit hard for you. (I audited her Math 33A class, and although I loved it very much (she just NEVER makes a mistake, which is unbelievable), I could expect freshmen complaining that it was very hard because Visan did a lot of proofs (the same proof I see again in my 115A class), but she does help lay a very very good foundation for math majors. Put in efforts, and I promise it will be rewarding.
Winter 2021 - As the person above mentioned, Visan is a really great lecturer. She's extremely clear and thorough during lectures, and goes at a comfortable pace (for the most part of the quarter). Her homework assignments are very challenging, but it really does help you understand the concepts. Plus, if you're stuck, she'll practically go through the solution with you in office hours. This class is supposed to be one of the most challenging undergrad classes in the math department, so most of the difficulty in the class should be expected. That being said, I thought her midterms were pretty reasonable and straightforward; all the points I lost were due to dumb mistakes. However, her final was more difficult (for me at least), although she did warn us about it. All in all, Visan's great, but expect to put in a lot of work into this class.
Spring 2021 - After taking Math 131ABH with professor Visan, I can confidently say that she's (one of) the best math professor I've ever had; her lectures are extremely clear, and homework assignments are helpful for us to truly understand our content. Also, she's always willing to help us when we get stuck on our homework problems. However, be careful about her finals; the 131AH final she gave was more difficult comparing to homeworks and midterms that quarter, and the 131BH final was terribly difficult. But this still doesn't affect the fact that she's an excellent professor.