When comparing Proggy Clean vs Apple Menlo, the Slant community recommends Apple Menlo for most people. In the question“What are the best programming fonts?” Apple Menlo is ranked 3rd while Proggy Clean is ranked 42nd. The most important reason people chose Apple Menlo is:
Equally well readable as Bitstream Vera/DejaVu Sans Mono, but with slashed zeros (aids with legibility).
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro The easiest to read
All characters are completely readable in the smallest size.
Perfectly usable in terminal and code editors in 12px text size.
Pro Hipster among hipsters
Even hipsters will marvel at this font, praising you as the new hipster lord. It is best at around 19px (tested on Mac). Overall, it has better readability than many default fonts.
Pro Great readability
Equally well readable as Bitstream Vera/DejaVu Sans Mono, but with slashed zeros (aids with legibility).
Pro Easy on user's eyes
Characters are very readable. They have consistent widths across all weights as to not break up words. Commonly used programming symbols such as various kinds of brackets are made easily discernible from each other and various punctuation marks are made bigger than normal. This makes them especially good for programmers who keep staring at code for hours.
Pro Clear differentiations
I, I, L, l, 1, O, 0, etc.
Cons
Con Pixelated
This is, of course, intentional; but it can be hard to look at compared to other smooth mono-space fonts.
Con Smallest font sizes hard to read
Fonts less than 11pt start to fail readability tests. 9pt specifically has an additional issue where brackets don't align.
Con Not really good in all font-sizes
Completely clean pixels, no anti-aliasing so its best viewed in (n*12) pixel size.
Bold font-weight is not really good because of small padding between them.
Con No bold version
This is not so great on a dark IDE, the characters tend to wash out, unlike something like Consolas.
Con Seems too wide at size 16
The letters become quite wide at size 16, impacting upon readability.
Con Doesn't work at size 10
Menlo displays as expected for size 11 and bigger, but doesn't seem to work very well at size 10. Issues include zero not being the same height as the rest of the numbers and Parenthetical Brackets not matching up perfectly.