I disagree with the review above mine. Ronchetti was by no means good at teaching. His lectures were unclear and extremely hard to follow. After the first week, I decided to read my brother's Linear Algebra textbook that he used at Berkeley and I learned a lot of the material ahead. So when I went to class and saw how Ronchetti would introduce a new concept, I honestly scowled. His way of introducing a new topic was terrible. I thought I could have taught it better. I did give him a 5.0 on helpfulness because he holds a lot of office hours, is a very nice guy, and will answer any of your questions (besides direct homework questions).
Now the worst part of this class was without a doubt the homework. It was unnecessarily long. There is no benefit in diagonalizing 4x4 matrices over complex numbers or doing least squares regression with numbers in the 100,000s. I will say that some of the proofs he put in his homework were actually helpful in preparing me for 115A. For example he asked us to prove that the eigenvalues of similar matrices are the same. This got me thinking about proofs in general and I am grateful for that aspect of the homework.
His tests weren't that bad (final definitely the hardest). If you study for them well and don't underestimate them there's no reason you shouldn't get an A-.
So yeah, main complaint is long/unnecessarily long/rote homework problems and unclear teaching. Pros: Good person, answers questions, extremely smart.