I ordered for some products through rediff last month.
The first order experience was good. I got all the 3 products on time. In fact they gave a good follow up. I got a mail when the product was approved by the vendor, when the product was dispatched and the courier details. After the product was delivered they sent a mail requesting for feedback.
I have seen lot of negative angry reviews also however I think it depends on the availability of the product.Moreover before buying the product please check the review of the seller. It will be available on the same page of the product. Then based on the review you can know how they are conducting business.