I am running 5 year old TEC-II hardware, upgraded with their new WinTec chip. Bought it used from Chad; so the price was right. Paid a top notch shop (Dynamic Motorsports in Dillsburg PA) to install it for me. The owner of Dynamic had just finished putting a TEC-II in his personal Quest! Even though I told Electromotive that this was purchased as a used unit, I am just stunned by the fantastic level of technical support I have recieved from everyone at Electromotive. They stopped at nothing to help me resolve technical problems that ultimately had nothing to do with the TEC-II unit or their software. (1 Jet-Hot coating on the downpipe interferring with the electrical ground of the O2 sensor 2) D@#% Compaq laptop that won't talk to the TEC)
Haven't had a lot of time (experience) in tuning it yet (with a borrowed Toshiba laptop); but I like it so far!
Proper fueling of an internal combustion engine is a very complex and sophisticated engineernig problem; a turbocharged application just makes it even more so. I am a techno-geek (degree in astrophysics) by nature, so this is the best toy I've gotten in a long time. If you are better on theory than on turning wrenches, this is the set-up for you!
From what I understand, the TEC-III is even more sophisticated in what it allows you to do.