FACT = From 2005. ICAI has changed its Pattern..Earlier questions used to be of 20 marks each..with less coverage of syllabus.. NOW ICAI give small questions and cover everything in paper.
So, Padhukas book is the best..No doubt
But simply ignore/Avoid Extra Complicated Sums( Which came in 90's era )
DONT EVER START FROM CHAPTER 1 - STANDARD COSTING ( Very Difficult and lengthy Topic)
Start from Last Chapter which will be from OR( Easy Topics and Small in size)
Study Theory Questions which came in previous exams..That is sufficient
DONT WASTE TIME ON BIG ( 20 marks) QUESTIONS ( Not required in new pattern Question Papers)