if people are used to serif, then garamond

but if people are used to sans, then scala

To answer this question, you need to include other variables, such as the measure—the length of line—and leading. Generally the problem on A4 or letter sized paper is that for a single column the measure is too long. And why do you specify 10 point?

At 10pt, I would go for Garamond (I am looking at the Adobe Premier Pro version btw). Perpetua looks great but has a smaller x-height, which probably makes it less comfortable to read.

Scala is beautiful and comfortable to read. It’s the typeface used by Ellen Lupton in her book ‘Thinking with Type’. Scala has a generous x-height and has contemporary qualities which I think is refreshing.

Check out Ellen Lupton’s website for her comments on the book and Scala.

It might sound like the designer’s disease*, but Scala may actually appear ‘too big’ at 10pt…

William’s right in that the line length and leading determine readability; Ellen Lupton’s book is not stationery-sized, and therefore her typography (including the choice of font and the measure) reflect this. In fact one could take any of Jeff’s four font choices at 10pt and make them all completely unreadable with bad-enough decisions on line length and leading.

Generally the software gives 1/5th or 20% the point size as ‘auto leading’ which is too close – particularly for sans serifs. The other thing, as William says, is that a single column on letter or A4 is too wide. For 10pt Scala I’d be looking at a line length of around 106mm (assuming everyday English, rather than technical English or a text with lots of long words) which implies margins of around 55mm either side on a letter-sized document.

*generally the client wants the text set bigger, the designer wants it set smaller…

Note: Scala is a serif face. Scala Sans is its sans-serif counterpart.