This is a quick review of my setup with 4 Eg4 6000xp connected to 2 Eg4 power pro batteries, needed to use 2 external busbars to make this work. Overall was very happy with this setup and excited to add solar but this setup is not UL9540 certified, which make it illegal in Phoenix, AZ; I will need to switch the inverters to the 18k to be able to proceed with my solar plans, tough lesson learned.