Originally Posted by victorczx3
about the chip... I was talking about the ones they sell on "EBAY" ...they claim same gains as an ECU upgrade...but for around the price I mentioned earlier...
I will go with my gut feeling and say they are crap right???...I would love to do an ecu upgrade...but will the additional Hps cost me more at the pump??? and do they have a negative effect on the life of the engine in the long run??? 
I have mixed answers for your question about the ECU software from e-bay... First of all, I have no idea which ECU software that you are talking about... It might be the BOSCH factory software that comes on a CD and includes all MB vehicles prior to 2006 and has various timing maps for each engine, or something else... Would love to help you, but I can't without additional information.
I will tell you this though, if you haven't done ECU / FMU, etc. re-programming before and you don't do it for a living, leave it to the professionals... Otherwise you're going to waste your $$$ / TIME and have your car sitting in the garage collecting dust while you try to figure out why it won't start...
It's not rocket science, but it is a process that takes a modicum of experience, knowledge and specific equipment that would cost you much more than $600...
Search this forum a bit more... You'll find your answers...