Awful
Adrian R Vetta who teaches Mathematics is a nice enough guy. However, the proofs you have to do in his exams are nothing like the relatively simple proofs you learn in his class. He delivers his lectures too fast. I could not keep up. His exams test your ability to discover algorithms on your own. Exams are averaged 60% before the curve for the rest of the students.
Average
The exams are extremely hard. The proofs presented in class are unclear. Knowing how the algorithms presented in the lecture is not enough.
McGill University - Mathematics