Help me choose books

I want to buy a book based on english asked in competitive exams(MBA,GRE,bank PO etc).I have seen two books ,they are :-
Objective English For Competitive Examinations by Hari Prasad
Flipkart.com: Objective English For Competitive Examinations 0070151954: Book: Hari Prasad (9780070151956)


and
English Is Easy by Chetananand Singh

Flipkart.com: English Is Easy 8190458906: Book: Chetananand Singh (9788190458900)
Tell me which one should i buy.
Also which english speaking course book is better,please tell me.
Should i buy a rapidex one??