There are so many different things that classify as “refurbished” nowadays that a large portion of the time the TV is essentially brand new. It varies from manufacturer to manufacturer though. Something as trivial as a MFR deciding to update the power cord, so they have to remove all the old power cords from their current stock and put the new one in. Well, to them it no longer counts as “brand new” so they sell it as refurb.
Don’t be surprised if you get the TV and it looks like it’s never been touched. I’m not sure about Vizio but I’d assume it’ll be in good shape.