Its not what you buy its where you buy it.
The very best or best price is not all that fantastic if or lets say when it needs replacement next time.
I picked a major store front retailer that has national coverage across the nation. What is even more important has a store close to the house for from this location is more than likely is where my experience as been is where it one has failed me.
The number two is to get the highest rated cold amps and aperies hours, they will last the longest and for the most part will have the longest replacement coverage.
My factory ones ( replace both batteries at same time ) lasted the three years plus two months, just outside of the 36 month coverage.
Replaced with the top of the line for about $30 total extra and got a 48 month free replacement ( not pro rated replacement ) with a 6 year warranty.
In Arizona for the most part the only last just over 3 years.