He's not as bad as people say he is. He's organized, concise, and the grading is fair. The final was a bit difficult, but everything is curved. I enjoyed his lectures and I'm taking 31B with him next quarter. It's not an easy A, but it's definitely not super hard either if you do your work!
His lectures are disgustingly boring, there's no point in going to them. His exams are unnecessarily difficult since he makes an effort to keep average test scores at around 60%. After the class got an average of 76% on the first midterm, he told us that normally they're about 60%, so the next midterm and final were. I don't think he's a good professor at all, he doesn't provide any knowledge that you can't obtain yourself from a book. If I were you, I'd avoid him.
this is possibly the hardest class i have ever taken in my life. the homework problems are hard but if you finished all the homework you should be fine on the final the professor is every helpful during his office hour however he is going to retire so i guess no students will come to check the ratings & comments
Liggett is a very good professor. But he is sooo difficult. Fainting level difficulty! I'm taking him for 171 while taking Math 170B Math 131A. My feeling that 171 with liggett is more difficult than Math 170B with Chayes and Math 131A with Stovall combined times 2... I literally spent all my time studying for Liggett (almost crying, occasionally) and I still got a B, while getting A for 131A from Stovall (people say she is hard, but her 131A is sooo easy compared to Liggett's 171).