Physics 7C and 7LC

Hi I am taking Physics 7C and 7LC with Xia and Tucker this coming fall quarter. How is the difficulty of the class? I was also wondering about buying textbooks since I need to buy one for the Lecture as well as the Lab. How often do we use the textbooks and Is it OK to buy an earlier edition of both and save money?

If you have any other advice about the class please post

thank you!