I have been buying a lot many stuff from amazon ranging from mobile covers to portable hard-disks and books. Till now, I am best obliged to amazon for their service and product quality.
Amazon is the world leader is books and provide very competitive prices.
Cons:
Overall, the products the good but amazon does not provide regular discounts to its customers or atleast to them who regularly buy from them. Amazon shall start issuing some coupons like Jabong and flipkart on app at least