E30/C220 Smart lock with rechargeable AA?

We have a couple smart locks with the rechargeable square batteries and 1 is not working anymore, so I am looking at the newer models which appear to run off AA batteries.

Eufy states 8 months with AA, however, I have seen a couple complaints of much lower times between new batteries or charges. I have also seen the rechargeable have less volts so it'll even be worse with them, but I wouldn't want to keep buying new alkaline batteries every month or two.

Can anyone with these smart locks, hoping using Amazon or Eeneloop rechargeable, comment if you are getting pretty good battery life? Or is it as bad as some people state?