Your batteries "seem" okay. Try a discharge test.
The advantage to lifepo4 is that they will happily keep with no charging for a year. If you don't trickle charge your lead acid. What would you come back to after a year? And in the event of a grid shut down ...
The lifepo4 may cost 4 times as much. but you need 1/3 the capacity or less. and they should last twice as long, at least. of course they are also far more efficient when in use.
Now if you don't ever use the batteries. Hey you can put in whatever. I've seen a guy using lead acid for 17 years. His 12kw battery now keeps 3 led lights on and allows 4 hours of tv watching per weekend at his camp. Before they "flat." He calls that "working."
But if you're using the batteries lithium is proven and tested to offer the lowest cost per cycle that you can buy right now. And a 12kw lithium system would run a small house for that weekend with lights, tv, internet, dishwasher, fridge ...
which is what I call working.