I agree with the principle of the buyer receiving positive feedback once swift payment has been made - he/she has fulfilled their end of the bargain and should be given due credit. Sellers who email saying please provide feedback once you have received the item and are happy should not in my opinion get any feedback as they are only prepared to aknowledge once they have received cash and positive feedback first. Put it another way - if you went into a shop and bought and item and the seller didn't save thank you for the business but merely handed it over without saying a word would you say thank you to them? Moreover would you go back and shop there again? Thought not.