Should I prepare from RS Aggarwal's Quantitative Aptitude book for IPM at IIM Indore/Rohtak?

Preparing from RS Agarwal will not be of much use. Because the questions in IPM or BMS exams are of a slightly higher level and involve more than just conceptual usage, but also a little bit of trickery. These are usually practical questions rather than theoretical ones.

These types of questions are not found in the books of RS Agarwal or RD Sharma. Rather, they can be found in books designed specifically for IPM or CAT preparation. You do not need to go for RS Aggarwal or RD Sharma, but rather for books that are specifically designed for the IPM or CAT entrance exams.