I agree with gurpreetsingh. Aristotle SC Grail
is indeed a very good book. However, it is only for those targetting at 700+ because it discusses quite a bit of grammar which is required to score 700+.
Instead of using either Aristotle
or MGMAT Verbal books, I'd rather prefer using both of them.
To begin with, you may want to start with MGMAT SC
Guide and then move on to Aristotle SC Grail