I agree with Fabiuz the concept as in the diagnosis where to get one not the other then it depends on what one wants to do and what to spend it...then you are talking of clones, around it you will find a thousand and at prices from discaunt but not always of quality, with risk of doing damage...relying on someone who maybe has something used but official because believe me, I burn an ecu is a nanosecond, and repair the damage sometimes it costs much more than a tool.
Ask for advice also to the administrators of the forum will give you straight good.