I usually buy lot of stuff online & have been an ebay member since around 2007. I bought almost 6-7 times on ebay & apart from 2 all other items delivered to me were either second hand / never delivered / chinese cheapo duplicate copies. Moreover, when I leave honest & negative reviews for a seller, they chase u like anything to get it withdrawn or atleast get it neutral. Bugged of it I do agree of neutral ratings, else they keep on calling day in & out.
Ebay boasts of some stupid guaranties; However things I ordered were below 500/- & repacking those huge boxes & then reshipping them back means courier costs & petrol costs approximately equivalent to item price, SO its useless guaratee for users who are looking for cheap deals on small retail items which are not easily available near you, Example - Massagers , shavers (u need to go to exclusive outlets) etc.
Apart from ebay, all other sites viz. flipkart , rediff, indiatimes etc. have their own warehouses & not just attached sellers with not to be located shops, places; hence better trusted.
My advice buy from other specialised sites which have their own warehouses, so that u can legally grab their collars if needed, ebay just direct you to seller who cant be traced if need be. This site is only good for buying items which are really unavailable in india, example like I bought - sanyo eneloop batteries some 2 yrs back which at time were not available in india.