Even though he has an spanish accent, his lectures are very clear and easy to understand. To give a different perspective on his exams, I think the midterm was fairly reasonable and many of my friends did well too. I can see however how it would be difficult for some.
There are 4 questions in the mid-term, and all of my friends can only solve 1 or 2 of them, but there is no curve. Assignments and quizes have nearly no relation with his exam, and his final counts for 50% of the grade.
Extremely challenging exam + confusing lecture + no curve = Raul. He is the worst professor I've ever seen. The midterm is extremely hard. I got A from Math4A to Math6B, but for Raul's Math6B, I'm wondering if I could get a C. If you want to destroy your GPA, select Raul.
Alonso is a very nice professor. He grades very leniently and is super helpful in office hours.
His ability to copy the textbook onto the blackboard word for word is honestly impressive. He's very nice and a reasonable grader but it's hard to learn anything through lecture. Sections are a lifesaver!