MS Word font size matching visually the LaTeX default one

There are at least two font families that are based on Computer Modern (thus match its metrics) and are available in the OTF format that can be used with Word:

  1. Latin Modern
  2. Computer Modern Unicode (also supports Greek and Cyrillic scripts)

Click on the font name you've chosen, then proceed to the download page and get the OTF files. Install them in Windows and Word will see the fonts. As you're looking for just a 80% accuracy, choosing the upright 10/12pt Roman font for the text will be enough.

I can't see, though, how typing text in Word is faster than in any text editor (maybe save spell checking).