I would definitely get EG4 over Expert Power for the reasons posted by other commentators.

Example kit:

https://signaturesolar.com/complete-off-grid-solar-kit-eg4-6...

Add in a 15 kWh module and it's roughly the same price with better customer service, reliability, less parts, etc.

However, I would just get an EG 18k PV, 45 kWh of EG5 batteries and 11.4 kW of solar panels from signature solar and that would cost you $18.5k