If Apple refurbed it, I wouldn't hesitate, provided that it is of fairly recent vintage. If it's too old, you'll run into a problem updating the OS and other software because it will become obsolete sooner than later. I have that issue with my late 2014 iMac (which I bought new as a refurb from Apple). If I want to go beyond Big Sur, I need a new machine.
Personally, I would go for the loan and buy a new iMac. Your call...