Which book to prefer ?

Surbhi Bansal is the best reference book for CA-IPCC

Other than Kamal Garg, I have gone through the rest and personally, I prefer Pankaj Garg. Audit at CA final, to be frank is boring. You need a book that can arouse interest and I think Pankaj Garg does that. Vikas Oswal I felt is very haphazard and Surbhi Bansal is decent but her IPCC book is better I felt. I am studying from Pankaj Garg and finding it very comfortable. He has covered most of the practice manual too so you don't need to refer it separately. So, yeah, my vote goes to Pankaj Garg.

I am so sorry. I thought you are asking for final. For IPCC, Surbhi Bansal is pretty good.

Pankaj Garg (best) or Surbhi Bansal both are good. 

But dont miss to read practice manual plz..