For direct taxes t TN Manoharan is exam oriented. Language used in Vinod Singhania is live conversational plus Professional it is good for theory and concepts, problem given in this book are not suitable for exam, it is very time consuming. If you need concise book for direct taxes then you can also see T G Suresh it is to the point. In my view TNManoharan with Vinod Gupta Summary Module is the good combination for DTx.
Best Book for Direct Taxes CA final is Singhania along with latest Practice Manual of DT and no doubt but if u want to exempt in that subject then u must prepare ur own notes from these books and revise daily for half an hour u will definitely exempt in that subject..