I can't honestly remember who turned me onto it but I started checking the JAW (just another wideband) out on http://www.14point7.com. I decided to get a JAW unit because it's cheap and it uses the same Bosch LSU 4.2 sensor that the AEM does (and I believe the PLX and Innovate do). With it I will be able to troubleshoot the problem I have with the AEM reading ~15.5:1'ish in closed loop. The JAW allows for free air calibration (the AEM and I believe PLX do not) as well as giving you data on the heater value of the sensor so it is easier to tell when the sensor is giving up the ghost. I just ordered it and I just ordered the bosch connector from tech edge in Australia and have a lot of work ahead of me when the parts do arrive but once I get it up and running I'll be able to see if I get different readings from it with the same sensor and then see how they change afer calibrating it. I really think the problem lies there (no free air cal ability).