Quote - Is there any real advantage to trying to actual render that large seems like post process would be a better idea....that has got to be a loong render...for something that size.

 

Well, If you render at a lower resolution then try to blow it up to a larger one to print it high res on poster stock, you lose a lot in the translation.  The software would have to interpolate the increase in res.  Rendering in a very high res to begin with means no loss of image quality.