2016+ CX-9 Owners - Have you replaced your battery yet?

2016 CX9 at 35,000 miles;
Purchased "new" and full warranty as mgr demo at 4800 miles. Battery still OEM but not sure how it tests. I will have dealer LOF and checkpoints this week and can update. I've been known to tender the battery of my two cars with a cheapy Harbor Freight motorcycle battery maintainer. Once or twice a year though. 🙄
Update: Last month I had my 2019 CX-9 GT FWD in for routine oil change and 15K service stuff. I've had the car just about 3 years at that point and I asked them to check the battery. The service advisor acted like I was wasting their time but when the performed the test the battery failed. They gave me a new replacement under warranty which still had 6-days left on it.
About time I replace my CX-9's original 6 year old battery as it's starting to show some weakness during cold startups. AGM is the way to go right? I'm looking at this Napa Legend AGM battery (640CCA/755CA) and the Costco Interstate AGM 35 battery (650CCA/800CA) which is cheaper. Never had a Costco Interstate battery before so not sure how good they are. Anyone have any feedback on them? Little bit higher CCA/CA on the Costco Interstate battery. I see Costco's warranty is a prorated refund versus an actual replacement for the Napa.

I had a Napa Legend in my small commuter Toyota for like 7 years and never had any issues with it and recently replaced it with the same model Napa Legend battery. I'm leaning towards the Napa Legend AGM I linked since I got so many years out of the one I had in my Toyota and because of the full replacement warranty. Any thought/suggestions?
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Cx9 2016, purchased used in DEC 2019. First battery replaced in 2021 Dec.
Then 2022 October. I noticed a butch with same sticker at Walmart, I think that was a bad covid batch. Having a Walmart battery died under 3 years is rare for me. As soon as I noticed a little starting issue, I try to warranty. If Walmart isn't willing to switch. I'll hold onto it a bit longer with two potable jumper ready on standby.
Nope. 21.5k on CX9 2021. On my RAM1500 which sits nearly the entire winter, I disconnect the battery, charge it up and store it in dry area for the season. If the mazda would ever get the same kind of hibernation, I'd certainly do the same and disconnect the battery and store it too for the season.