Indeed, the Tesla powerpack is years ahead of the competitors, probably because they engineer only the hard parts themselves and use commercial products for the easy stuff.
Do you have a source for the “years ahead”. Not being sarcastic, I’m genuinely interested.
It's my opinion, mostly, but I've written drivers to control several different models and makes of battery installation, so firsthand experience. The difference is in the control software and reliability: Tesla batteries are way more reliable and have less downtime than anything else I've worked with. It's getting better.