Hello.
For the preparation of JEE advanced , both  books and coaching material are good , but it depends upon the choice of student , coaching material includes main and important content of topics while books includes detailed explanation of topics along with these important concept, you can first go with the coaching material if you get any doubt then clear from your mentor (if available) else you can clear from the books also, instead of this if you directly jump to the books then it is again ok but don't deviate your mind on two or more source just focus on  one at a time.
Best of luck.