Really unless you want more power then stock you do not have to mess with them. But guys like me do want more so we have to come up with things. I was just pointing out like it was pointed to me that O2 sensors degrade over time and as it degrades it gives false readings which changes things eventually for the worse. This is why having them done on a dyno is good as long as the dyno operator's Sensors are not degraded. then once installed the tune stay pretty much the same not something that keeps adapting over time and eventually might not adapt as well as when new. Npt to mention is the O2 sensor accuate to start. I know the Innovate is off a wee bit when new so as it degrades it will be off even further. I have used the innovate and the Weggo brands and they are nice but I did end up buying new sensors to make sure they were still as accurate as when they were new. Just something to keep in mind.