[K3CAL] Battery Inverter Generator Recommendations

[KB3WFV]

I have been looking at Battery Inverter Generators for back up power use. These are gas-less power sources that can be charged with a solar panel. One source that I see the most is 4patriots.com. 

Does anyone have any experience with these types of back up power devices?
Does anyone have a recommendation for a source or a manufacturer?

Brian
KB3WFV