PCM Diagnostics & Tuning - LM-1 sensors dieing fast?

Anybody have an issue with the O2 sensors going bad fast? Maybe it's because I have been using the VW sensor, but my original sensor worked for something like 3 years. Then I replaced it with a VW sensor. My 3rd one just died (erratic readings then Error 08 Sensor Timing), and none of the VW ones have lasted more than a month, 2 of the 3 didn't make 2 weeks I think. Any ideas?

Isn't the VW Bosch sensor the same one supplied by Innovative? Overly rich, lead additives or oil consumption will shorter their lives. Also, no or inadequate 12V to the sensor's heater circuit will cause premature fouling.