I love technology, engines, machines. But the Onan 4000 is my least loved RV system. Noisy, smelly, and hopelessly obsolete by today's tech standards. The solar system has cut run time on the Onan to times when I need the air conditioner (mostly rest stops), and to exercise the thing. Even if the generator was modern, barely hummed with clean exhaust solar is a perfect RV system in suitability. Especially for the boondockers in this forum. Yep the generator is still there in a backup capacity but it has mostly been pushed off the table.