I am looking at 48v rack system batteries. I was set on the Signature Solar EG4 lifepower. Until I just came across Sunpowers 48V 100AH Server Rack LiFePO4 Lithium Battery SG48100P... they are running a sale and they claim FREE shipping. I put the thing in my cart and it says free shipping, 15% off which brings total cost to $1402.59 per battery. Claiming 10 year guarantee which is 5 years more than the EG4. I have a victron inverter which will require buying the $100 eg4 communication hub, The sunpower may not need that .....not sure. Shipping on a single battery from signature solar shows $260. Can I hear the communities opinion. Much appreciated.