Dimension in paper or model space ?

There are pros and cons to each method.  Best advice is to take a typical drawing, make a copy then dimension one entirely in model space using annotative scaling and the other dimension entirely in a layout.Our company places all text and dimensions in the layout.  Model space is reserved strictly for geometry.

Fair comment , But using annotative dimensioning and notes in model space allows (when required to coy complete details from one drawing to another and then you don't have to re dimension in paper space , as once was said to me 5 and 4 equals 9 , but also 3 x3 = 9 , both are correct

If you had already made up your mind why bother asking the question?  Every user should test both methods then select the one that works best for their circumstances.