taahir1981

Hey @taahir1981, the benefits are quite simple. With an additional 3kW of capacity, you can support a larger load. My friend has an 8kW ESS and he can boil the kettle and run the rest of his home without having to disconnect certain high current appliances. Things with a coil or element need a lot of current, most 5kW inverters use their entire capacity running lights, PCs, internet and all the usual odds and ends but boiling a kettle as well can be a little too much.
Its more of a safety and re-assurance thing, you are unlikely to hit the inverters max unless you're using geysers etc at the same time. Plus, having an inverter operate at under 50% usually leads to better efficiency. If you want more solar power, the 8kW will likely have a bigger MPPT. It's more about future proofing, if you have the money and want to be completely uninvolved with managing the system then go bigger. If you would rather spend a little less and take a minute or two to check load levels etc, the 5kW is probably the better choice.