I'll agree with the majority of posts regarding fake clubs on Ebay. I have one negative feedback in 2500 - which was received from someone who sold me a fake club!
There are no hard and fast rules to determine a fake - ie serial number on a Callaway 8 iron - some real ones have it, some fakes have it and vis versa. Not all genuine ones have a serial number - if they are UK bought they generally do - but the demo sets that go out with any new launch to pro shops don't always - and some sets from overseas don't - but they are genuine! One of the biggest tell tales on the majority of fake Callaways is the through bore shaft - you can see where the shaft comes out of the iron head on the underside - on a lot of fakes this is a plastic plug rather than the end of the shaft. You can tell the differrence between real and fake but you have to have a look at them and compare to the real thing - so never buy from someone who you can't confirm their address, never buy from someone who won't let you pick up your item - postage of golf clubs is expensive (unless you are a large account holder with a major courier) so save yourself some cash by picking up. Or at least ask if you can pick up - if you can't - stay away - either the seller has something to hide - or you are not important enough as a customer for them to show you the goods and talk to you!
I can't stress enough - as stated by so many other members - if the deal is too good to be true - its probably false. The big makers do not even sell their goods to their largest suppliers for the prices seen on Ebay! Callaway do not allow their approved retailers make as big a margin as you would think on clubs - infact the margin is very small with the bigger margins coming from other goods that come at much cheaper prices as part of the retailers package with Callaway.
Why would you want to buy a new set on Ebay - if they are genuine current model the most you will save against a retailer is 10-15% - not worth losing your warranty for.
The real bargains come from sellers like me - 2nd hand - prices have been driven down by the volume of fakes sold on Ebay! You buy from me you can pick up, come round and see before you bid, if you win you are supplied with by address which is a verified paypal address, telephone numbers, £500 paypal protection, my bank details, tracking for your parcel etc etc - make sure anyone you buy from is open and honest - it only takes a few questions or bluffs!