My Seagate SATA harddisk was broken last month and after a few weeks of wait, the replacement is finally arrived.  I am very impressed by the warranty service offered by Seagate.  No recipt is required, which otherwise could be troublesome since I may have lost the recipt.  The warranty service is completely self-service online.  All I have to do is enter the serial number of my harddisk﹐ check whether it is still under warranty.  If the warranty is not expired, I can open a service ticket and then send in the old harddisk.  No question asked.  It is probably the best warranty experience I ever have.  Unlike other warranty service which attempt to repair the problem, which may take up a few months, Seagate just send me a replacement unit, which works just like a new one.  Here you have one happy customer.  When I buy harddisk in the future, I will consider Seagate first.  I think this should be the standard for all warranty services.  Warranty should be covered by the manufacturer, not the import agent.  As long as each product has a unique serial number, there is no need for the proof of purchase.