Polar power and similar 12VDC generators
 

I have come across this manufacturer, who makes a several 12 volt DC generator sets:

Generator, 4 to 14kW Propane/Air Cooled

In short, they have a product built from the ground up to be a high-current DC generator directly driven by a gas, diesel, or propane-powered engine at moderate RPMs. They have controls that provide current and voltage limiting and which adjust the engine RPM based on load.

I think the central premise of what they're doing makes sense and am a little surprised that these machines aren't more widely sold in the RV market, though the high cost is part of it.

Anyone seen one?

What do you think?