Dear Gaurav,
All the Universities you have referred to are good schools and one, Durham, my alma mater from my first law degree. Rather than trying to direct you to one or the other let me give you a few pointers so you can make your own decision.

For the courses you are interested in I would check
1. How many courses are running in the subject? EG if you are interested in international many courses in international trade law are on offer.
2. Do the Professors teaching have any specialism in the subject? Easy to check on the web in terms of articles and conference presentations.
3. What access do the Universities provide to the profession? Do they have practitioners and regulators giving guest lectures or teaching on the some of the LLM courses.

I hope the above is of help
yours sincerely

Professor Alan Riley
LLM Programme Director
City Law School
City University
Grays Inn
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