LLB is sufficient for practice but if someone want to do specialization in a field he can do LLM.
As for as benefits are concerned, i guess most of the Multinational companies prefer LLM lawyer. Moreover, if you are interested in teaching you should be LLM i.e Lecturer of Law in a university.
But if you want to practice and are interested in earning money then LLM can give you edge because you can work as a visiting faculty in a University with your practice. Take example of Islamic University Islamabad, many Lecturer are visiting and are practicing in Islamabad/Pindi High courts.
Those who are asking about institutions of LLB.
Here goes my ranking list of LAW institutes.
1) Quid e Azam Law College (QLC) Private owned, expensive but good one.
2) International Islamic Uni Islamabad ( As many as 150 students were enrolled in Fal 2013, which includes 30+ students from Sindh,Balochistan)
Quid e Azam university is also offering LLB.
3) University Law College Punjab University, If you are interested in CSS this institute can train you for exam. ( A friend of my uncle, who manage to score 51% in LLB in PU was among the lucky 238 qualifiers of CE-2013, this tells you the efficiency of PU student but there are always exceptions
JAMIAT HAS INFLUENCE IN PU sooo....
Other then this Q.U is also offering LAW from 2013 but only 5years.
University of Sargodha
Bahudin Zakriya Uni
Rawalpindi Law College
Pakistan Law College