Uhmmm usable...just the other day making coffee using the Mr. coffee 12cup and then run the microwave 4 minutes making breakfast at 30% SOC before the sun hits the panels. Roughing it off the beaten trail. ;)
Edit: I suppose a little data needed.
Before microwave use,
31% SOC, lfp pack 13.06v,inverting 12.9v (@ 9a)
Tail end of 4 min microwave use,
30% SOC, lfp pack 12.66v, inverting 12.4v (@ 148a)
1 minute after microwave finished,
30% SOC, lfp pack 12.99v, inverting 12.8v (@ 9a)
I set the inverter for 12.0v disconnect.