I took him for LS40 (new life science stats). He's a great guy and genuinely wants his students to succeed.

The course is based more on the procedures of different statistical tests rather than actual math. On the exams you need to know when to use which type of test to use to analyze different scenarios that he gives you. Both the midterm and final were open note, which definitely helped a ton, but you still need to actually understand the material since you can't really to regurgitate stuff from the notes blindly and expect to do well.

The labs are easy and the TA's are super helpful.

Overall I'd definitely recommend Guillaume, he's a really friendly, approachable, and engaging guy.

This is a review for LS40, the new LS stats class.
I would recommend taking it with Guillaume!
Obviously you are learning stats, so it is nothing that complex. But rather than learning how to do actual math, you learn about different types of graphs, different types of tests to run, etc. and what occasions to use each. The exams are more like asking, "What type of graph is suitable for this data? What does this distribution say about the data? What type of test should be performed on something with 2 independent variables?" etc. and very little actual calculations .
Like the LS30 series, you have to learn how to code, but I found it a lot more easy and fun in this class. Guillaume made the homework fun, by doing things like having you perform statistics to solve a murder mystery. And if you are having trouble you can always go to one of the TA's office hours to make sure you get full credit.
Both the midterm and the final exam were open note, he let us print as much notes as we wanted. Hilariously, he had a crossword puzzle on the midterm, and a word search on the final.
I would say the class is completely doable and possible to get an A, don't slack off too much since it's stats, but make sure to understand the different types of graphs, tests, etc.
Btw, he is a pretty good looking man with a French accent for all the girls/guys out there into that ;)