Re: Kinda OT Oxygen sensors
They deteriorate with age. They can also become contaminated. In general, newer vehicles, where nothing has been done to hurt the sensor, can go well over 100K miles. The so-called 'tune-up', today, for modern cars, includes a quick test for 'sluggishness' of the O2 sensor. If the sensor has become 'lazy' (trade-talk), it is replaced. Volvo (first to widely use the sensor) originally recommended replacement at about 25 or 30K. I've personally run a Volvo well over 100K, checking the sensor often, and never had a sensor problem.
I haven't looked at the reference site... I will check it out.