Till now I have purchased more than 100 products mostly electronic products from amazon.com. Not a single product is bad quality.
Each time I purchase its a satisfactory deal in terms of time of delivery, quality of product, quality of packing, customer support. I dont know how their return policy because not a single product I have returned yet. Another good thing is amazon has good control over its sellers assuring you the quality and originality.
I will say it is the best online shopping hub with the largest veriety of original products.