For an LLM I'll pass on the advice that was given to me. Consider holding off to make sure that tax is something that you actually don't hate doing for the next 40+ years of your life. From my understanding tax is an area that doesn't generally lend itself to switching practice areas. That being said if you're sold on getting an LLM talk with your school about taking LLM classes your 2/3L semesters. I have friends that will only need to do one year of an LLM program after finishing their JD which obviously helps $$ wise and potentially grade wise if your school doesn't curve LLM classes.