Question about Seagate IronWolf

Apparently the ST8000VN004 is the newer model and the failure rate has been reduced from MTBF=1Mio hours to MTBF=1.2Mio hours (in practice this will play a minor role).
https://www.hardwareschotte.de/produkt-ve...

Here's what strikes me. The question here is about a product that is obviously a return, which is why it says as new and tested. In addition, this product only has a 1-year guarantee, whereas item 12243540 has a 3-year guarantee.
Since item 12243540 is also cheaper, it would be clear to me which item I would buy.
I don't see any difference in the technical data. The different Seagate number can have various reasons, e.g. one could be a newer series or have been manufactured in a different factory. Only the manufacturer can give more precise information.
I have 4 such discs in my NAS and so far they have done their job without a sound. For over 2 years. However, I have the model ST8000VN0022, the more expensive one, which is also on this page.