On this topic, having just replaced the same sensor on a friend’s Audi A3 TDi a couple of weeks ago, I learned that you can bring old ones back to life by heating up with a gas torch. (You also need the hands of a child to work on that engine)!
Apparently they get “clogged” up with soot inside and once you burn it off, they go back to normal. There’s a YouTube video of a guy who gets his glowing red and shows how it comes back to life with a Volt metre. I kept the old one to try the same when I get some time.
In this scenario a bosch one from GSF was only £70 (with discount code) so it made sense to just replace it for a reliable commuting car.
Edit: the gsf Bosch one looked identical to the one that came with my Innovate AFR. Also here’s the link to the YouTube thing I was referring to (there are many more claiming the same):