I recently purchased two SOK 100 Ah batteries...haven't fully tested the battery, but the capacity test appears to be good (1300 watts each on initial test). I haven't conducted a full Current Load test to see how hard I can pull amps out. Charging seems to be good with 40amps going in, but I'm using an EPEVER 40A, and the SOK recommends 50A charging. I just received a 50A/60A charge controller today, and will test tomorrow on the SOKs. I believe Amazon just raised the price to $640, so going to the SOK site or eBay is probably the best price. SOK I believe will not charge tax (depending on where it is delivered). I'm not saying that these batteries will beat others, just letting folks know what I'm doing, and will let you know if I run into issues. So far no issues. I doubt I'll do a teardown (for now) since these are perfectly good LiFePo4. I've seen the YouTube teardown review, and am satisfied with the construction and configuration. I also have seen a YouTuber change two old SLAs for two SOKs, and the SOKs seem to be operating sufficiently.