What is Reddit's opinion of Denso 234-9052 Air Fuel Ratio Sensor?

From 3.5 billion Reddit comments

I may just rreplace the upstream one.

Probaly my best bet after looking around.Remember Canada here.

https://www.amazon.ca/dp/B0018JSH02/ref=au_as_r?_encoding=UTF8&Make=Toyota%7C76&Model=Yaris%7C2851&Year=2007%7C2007&ie=UTF8&newVehicle=1&vehicleId=1&vehicleType=automotive

Quote from someone @ yarisworld

( if replacing the oxygen sensor before the catalytic converter. The second oxygen sensor after the catalytic converter only tells the computer that the catalytic converter is still functioning but will not adjust air or fuel mixture.

That's why the first oxygen sensor is often referred to as the air fuel ratio sensor.