LiFePo4 cells

I could not find any good info on them, just what wiki told me and some bits and pieces on this forum.
Due to a other post this triggered my interest:
https://www.aliexpress.com/item/400...&terminal_id=4866f489536f4ed88bb42955f2a61510

Could this be something? is it worth to save money for?
When i did some calculations those are cheaper in the long run? vs second handed 18650.
Has anybody tried them or tested them?
Is it wise to buy one, test and hope they are delivering with a big order the same cells?
Or take a shot at it and hope for a bullseye?
You can buy also a bms that goes for the cells capacity(twice bigger if you want).

Can those be integrated in a 18650 li ion powerwall?
With there own bms? or stick with longmons?
More questions than answers, any thought or suggestion would be welcome.

Anyway any info would be welcome and very appreciated also on regular/normal lifepo,thanks in advance.

All great questions. I could never get a clear answer and so I went 18650 and hope to prolong their lives... sad since I love the idea of LifePo4 or LTOs.