Theres two different things going on here.
You have a lead, and a piece of software.
When you buy a genuine lead, from rosstech, your not only buying an interface are also buying a licence to unlock the software and use all its functionality, ie logging etc.
When you buy a clone lead from ebay, your only buying the interface, and an old one at that (ie it will only talk to non-CAN vehicles and is much slower for logging etc)
Rosstech offer a free version of their software which is limited in capability and can be used with an ebay lead, again this free software isnt comparable to the full thing, but for a lot of people is more than sufficient.
The last option, is to buy a ebay lead, and a licence from rosstech. The licence costs $100, and gives you most of the functionality of the full shebang but with the ebay cable.
Its not really fair to compare the £240 genuine cable with a £10 ebay lead, because they're not the same thing.
Personally, for older cars like ours, i think the ebay leads are fine. I've never had mine break, but even if it did, i could buy quite a few of them before i was up at rosstech money. An ebay lead and a licence from Rosstech gets you all the functionality you will ever need on a B5 model, will cost less than £100, and rosstech will also refund the $100 you paid for the licence if you ever decide to upgrade a real cable.
Theres one caveat to all this, which is the hacked ebay cables which are designed to work with newer versions. These are in effect illegal, and this is why they get locked when you use them with a newer version of the software. I wont condone their use, but ofcourse its up to the end user if they wish to use one of these. The ebay cable i use is just a simple dumb interface, and only works with 409 or VCDS-Lite, but thats fine with me.
NHN: You need to step back a minute and see both sides here. If you actually took the time to explain all the options, and how each option differs it would stop you coming across so badly. Genuine leads simply arent for everyone. Theres folk on here who only paid £250 for their entire car, and they simply cant afford nor justify spending the same again just to flash out a fault code.