I took a year off before coming to Columbia and was about to drop this class because I hadn't done calc in a long time but I'm glad I took it looking back. My calculus skills were rusty so I decided to review basic calc before entering the course. The lectures aren't helpful at times when they we go into proofs since the homework and exams are more application, so I learned mostly from the textbook. He is very fair with the exams- the can be difficult simply because they are difficult topics but he will not throw you with surprises. The practice exams are just like the real thing; expect to work a lot with friends and searching up stuff online. Overall this class is for people who are hardworking, dedicated to UNDERSTANDING math and not memorizing it.
TIP: find a calc buddy or two; it'll make everything much better. Oh, and also know that many steps are skipped when he writes things on the board so be prepared to catch on fast