Interesting unit. I hadn't run across them, though they've been available for a couple years. Looks like their efficiency improvement, reduced fuel usage, and "quieter operation" comes primarily from a significant reduction in the engine size--about 30% smaller than the Onan 4000.
Because they incorporate an inverter unit, in addition to lower harmonic distortion they can run at variable RPM (2200-3600) for lighter loads as opposed to the constant 3600 of the Onan. That should help the noise environment as well. That also allows them to energize the main generator to start the engine rather than needing a separate starter motor.
This is overall an advanced design incorporating newer technology over the venerable Onan 4000 RV generator. Based on advertised price, they've done it at a cost lower than the Onan. I think about the only thing remaining to assess is long-term reliability, and that is just going to require time to see how well they hold up.
Mike
