I didn't see a price for the system.
The real question isn't how much degradation you have during first 5 years but what is the degradation curve and what is it like in 20 years?
Thing is, batteries are often times over-provisioned, 100% is closer to 90%. So your first 5 years of degradation could simply be the provision so it seems like 0, the drops.
If they give out a warranty then it is likely to retain 80% capacity during the 20 year warranty period. Even first LFP batteries had a very good longevity. They could easily last > 10 years if managed correctly. So this is not out of the ordinary for updated tech.
Cost product and install cost and diy ability?
This can be a big move into energy storage, where supply can be temporarily installed, removed to another site, or trains transporting the storage to site of usage?