This is interesting. This guy does a capacity test on his 15 year-old Lifepo4 bank and it still delivers 400Ah.
I like his straightforward no nonsense approach.
Having recently upgraded from Epever SCC's I had always thought in terms of their 1.5 times max of oversizing of PV relative to the max output of the SCC.
But I was playing around with Victron's MPPT calculator recently and it seems like they are happy with substantially oversizing the PV array...