After talking with the Powerchip people for over an hour on the phone I decided to try the upgrade. The cost: $690. Removal of the ECU was simplistic and will be in the mail tomorrow. Since it will be over the weekend I will not receive the upgraded ECU until Tuesday afternoon. I will post a review of the improvements. For those interested I chose the Powerchip Gold93 version of the upgrade. It has a 3 year warranty and a 14 day moneyback guarrantee if I don't note any improvements.