MilwaukeeS4

So I recently purchased my first S4 (2001) and I purchased it with a CEL for a bad O2 sensor. The code is P1118 which is the passenger side downstream sensor. Details say that the heater circuit is open. I've been searching for the correct replacement part, and came across these o2 sensors for a very low price.. Just wondering if anyone has any experience with them, and if would not recommend this, then if they could point me in the direction of the part they would use. I'm also curious if the upstream and downstream o2 sensors are the same? Because I've looked and seen both have the same part number... Sorry for sounding like a real idiot but I am slowly learning everything I can about this car and want to make it my project build, and want to do as much as I can myself. Thank you for any feedback or help!

Here's the link to the o2 sensor I was talking about.

https://www.am-autoparts.com/2001/Au...FQyHaQod1ioC7g

2001 Audi S4 Downstream O2 Oxygen Sensor for V6 2.7L Turbo at 1A Auto.com