mwebb -
The digital AFR proves what I want to know. It shows the "cold 02 sensor" go from the 0.5 signal from the ECU/PCM to a lean condition as it warms up. Going lean with the engine off is the proof I need.
I got advice from a dude that works for NGK(NTK?) :
Using heated 02 sensor in place of non-heated 02 sensor? - SaturnFans Forums
Start reading from post #23 and you'll hear what he has to say. His handle is "NGKTECH". He has run my setup for a couple of years without problems, and others have done the same. That *doesn't* document miles, but he appears to come from the harsher climate of Michigan.
Like I said, I'll take the hit if it doesn't last too long.
CarloSW2