I'll start out by saying I came in the second week and didn't get the book until the 4th week. I really liked him and his style of teaching. I only feel asleep during one lecture so all the rest were pretty exciting for me... His lecture is identical to the book so you can really do one or the other. I got an 'A' in this class and I never read the book (shouldn't have even bought it) but I did go to most the lectures... THIS IS A MUST TAKE CLASS FOR ANY ECON MAJORS GETTING A MINOR IN POLI SCI!! The second half is all econ and at least for me having a background in econ (and other poli sci courses) made this ridiculously easy cause it was all review. Overall I would say this was an easy class and would recommend taking it. Just dont take it to serious cause its really pretty easy.
I thought Trager was alright. I had him for Poli Sci 20 Spring 2010. He reads of his slides which makes lecture pretty boring. He is a nice guy overall. If you go to office hours he really tries to answer your questions and appreciates references to course readings. The class was a midterm, final and a paper. There was a big time crunch on the midterm when he said there wouldn't be. The final was ok, not nearly as bad as the midterm. The paper was cake, but the topic was not that interesting. He had you turn in a first and second draft of the paper each worth 10%. It was just like a guarantee you would get a higher grade on the second draft. This class was fine, not the most interesting but overall it was ok.
Fall 2021 - This class is supposed to be a seminar class (30 students taught directly by Traeger). But due to a "department error", when I took it (Fall 2021), it was structured as a lecture with circa 100 students and 2 TAs. Traeger is a fairly run-of-the-mill UCLA Poli Sci Professor. He's clearly brilliant and accomplished, but he imbues the same “I have plenty of important things to do, this class is largely an errand” attitude as 80% of the tenured political-science faculty here do. Readings were heavy and didn't feel particularly well organized. Lecture consisted of him loosely ranting while slides were largely blank (containing of only a few words or unlabeled infographics). If you asked him a question that was related to something remotely logistical, his response was always “just ask your TA”. He also canceled class... twice. He'd make efforts to rile-up enthusiasm (he often posed open-ended questions to the class), but they usually fell flat. Grading-wise, the syllabus initially consisted of 2 prompt-less short papers (4-5 pages) that correspond to 2-week's readings of your choosing (basically you just discuss the readings or tie them together, not always easy). The final was originally a 12-15 page no-prompt research paper, later shortened to 10 pages by our TAs. This was pretty hellish and unclear. The guidelines were to develop an original international relations theory and devise a statistical test to see if it's legitimate. That approaches graduate-level work and was super difficult. Thankfully the TA's went pretty easy grading wise. I have a feeling that Traeger's grading would've been different. This class was fine in lecture-format (with TA's as graders), but I have a feeling it would be much harder and more unclear with Trager as it's main instructor. I would avoid this class in general-- especially if it's in a seminar format.
Trager is one of the most intelligent professors I have come across in my time here at UCLA. While I did not take his PS courses that are more "traditional" for your typical PS major, he has superior command over mathematical application and formal analysis of political science. Taking 204 with him has made me reconsider a PhD program (instead of law school) due to his teaching. I have a lot of friends who heavily criticized his PS 20 and PS 129 courses. I assure you, if you have a genuine interest in learning the material he presents, you can take away a lot from his class. When I was in his class he always made time for questions outside of class and was always very enthusiastic in discussing course material with me. I strongly recommend taking a class with him if you get the opportunity.