Dear aspirant

Both the books are of almost same level and contents are also same. Also both are very easy to understand. Main difference between both the books is that in BDC topic are explained in theory and paragraph manner and same thing in vishram singh in explained in point wise manner. Vishram singh is more exam based book in compares to BDC.

So from my suggestion before buying any medical books if you are confused then go to your college library issue the author you want then study for 2-3 day from both and then compare it. Once you get confirmation that which book is suitable for you can buy that book. Also you can always issue any authors book from college library so make use of that. Most of medical college students prefer books from the library and use it.

Hope this information helps you

All the best