According to me compiler is good buy as it has lot of past year questions updated with the amendments and also 2-3 page summary before evert practical question section.
A day before exam u won't have time to go thru that big book and compiler will become handy and extremely useful. Therefore, I recommend.
@ rahul verma its from the same author..bangar has two editions one is comprehensive one nd the oder is compiler which is summary of the topics nd past exms questions. ..indeed best book for idt