Well, its especially a waste or time and money when you don't even put it on the right applications. MAF sensors are calibrated for the application they are intended for. This means you can't just take a MAF made for a car and swap it onto a truck.
The MAF may never wear out, its just one of those things that may or may not fail. If they fail, its often because crud has gotten through your filter and damaged the element. Oil vapor can also get on them over time. It really depends.
Apparently, the small V6 for F150 and Taurus DOHC use the same MAF. Rockauto sells the same part for both. I verified it from the Ford part number stamped on MAF. And DOHC Taurus is ay every corner of a JY but small V6 F150 is almost rare to find. Interchangeability is not the issue.
Good to know MAF DOES NOT REALLY WEAR OUT. That's what I wanted to hear. Thanks.