Both the courses are very good. If you are certain that you want to go for the LLB course and want to become an Advocate/Lawyer then my suggestion will be you should go for the 5 year Integrated course. The reason behind it is 'time'. If you go for the integrated course, then you will save a year of time and you will get the degree and you can start your professional career early. So if you are certain that you want to do LLB and you want to make a career in law, then going for the course of 5 year Integrated LLB is the best for you.

Now if you are no so sure about the LLB, and you want to try out different other things, or you are not sure that you want to make a career in Law only, then my suggestion will that you should go for the UG course and with in this 3 years you can explore yourself. And after that you can pursue the 3 years LLB course if you find yourself into it. For this case, 1 year of time may feel like extra for you, but you will be sure that what you are doing, you really want to do.

For more information regarding the career in LLB(you can follow the article also for the Integrated case as well) consider the link below:

https://www.careers360.com/courses/llb-bachelor-of-legislative-law

I hope this helps. Wish you a great eve!