Do not leave your brand new printer on. Turn it off overnight!
The reason everyone tells you to keep printers powered on is for the benefit of the ink sub tanks. This is a real problem for Oce/Fuji printers because the tanks are made of PVC and heating up and cooling down day by day may cause seal failure. As a result, the ink system may suffer from air leaks and dripping ink. But this is still a minor issue compared to the possibility that air will get into the ink supply system through the printheads and cause serious nozzle clogging, especially with original OEM ink.
Keep the printer turned off to keep your sub tanks in good working condition.