This question already has an answer here:
It seems to be the de facto standard to use
\mathrm for upright letter notation in math mode as opposed to
\text. Would it not be better to use
\text in general?
One particular problem I am thinking of is when writing in a sans serif-style document (e.g.
beamer). In many cases here, your text and math is set in a sans serif font (for screen readability, I guess). Using
\mathrm in this case causes the argument to appear in a roman font (with serifs), whereas using
\text seems to correctly pick up that the text style in the document is sans serif and display the argument in upright sans serif.
So, would it not be better to generally use
\text instead of
\mathrm for "upright" notation in math mode?