Review from a student who took M 408K
I had Xia in Fall 2004, and what you need to know is that he has a relatively strong accent, but after about a week or two, you can understand him fairly well. Overall, M 408K is hard and Xia's notes are pretty structured. He goes by the book, section by section in order. He even does homework problems at the end of class for anyone who speaks up. On tests, be sure to ask him questions, even in the exam room. He'll usually point (literally) you in the right direction if you pester him enough. To be honest, there is no easy way out of calculus, so you're going to be working extra hard (unless you're naturally good at math) no matter who you have. Xia is a good teacher to approach with questions and such.