I use a cheap cable and its fine.
You have a few options with the software:
Cheap ebay cable and the free software will get you the basics, you'll be able to pull and clear fault codes and probably view some other bits and bobs in the ECU.
To get all the features which allow you to log data and recode components, you need the full version of the software.
You can either pay $100 for a licence to use the full version to use along with your cheap ebay lead, or you can pay $250ish for a full kit which comes with a genuine rosstech lead and a built in licence.
The differences between using a licenced cheap lead, and the full genuine kit on a B5 are minimal at best.
I suggest you start out by getting an ebay cable and having a crack with the free software, as tbh it will do most if not all of what you need from it.
One useful offer is that if you buy the $100 licence, and then decide you want/need to upgrade to the full kit later, rosstech will discount the new purchase by the $100 you've already spent, so chosing to try the full software on the cheap lead wont leave you out of pocket.
NHN: Given that Rosstech themselves actively support people using the free cables (in so far as making the software available for free and offering the licencing only option for users of the cheap cables) i think its a bit pathetic that you cant just spell out the options like i have done, instead coming out with the "i dont do cheap cables" crap.
If you actually took the time to explain the differences and show them why they might find the genuine article a better buy then you may infact get more sales.
If you were to walk into currys and ask for a cheap tv, and the salesman said "ram it, i dont do cheap tellys" and walked off, i think you'd be walking streight out the door. OTOH if the salesman did his job you might walk out the door with a 42" panasonic plasma instead of the cheap set you were originally wanting.
