When comparing Envy Code R vs Monoid, the Slant community recommends Monoid for most people. In the question“What are the best programming fonts?” Monoid is ranked 19th while Envy Code R is ranked 23rd. The most important reason people chose Monoid is:
The user can adjust letter-spacing, line-height, and choose alternate characters prior to downloading.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Clashing characters are easily distinguishable
This font offers very distinct programming characters that help differentiate the following clashing pairs: {} vs. (), "0" vs. "O", and "1" vs. "l".
Pro Easy on user's eyes
Envy Code R is quite narrow (like Anonymous Pro) but at the same time squarish. The letters are easy to read and offer a pleasant reading experience.
Pro Fills out the space well
Envy Code R also fits more into a given width when compared to Source Code Pro.
Pro Bold font is the same width as the regular weight font
The bold version has the same width as the normal version which is useful for syntax highlighting.
Pro Customisable
The user can adjust letter-spacing, line-height, and choose alternate characters prior to downloading.

Pro Novel use of ligatures to display ascii character combinations as symbols
The common expression '!=' is displayed as '≠', '>=' as '≥' *, while maintaining the fixed width double-space that these characters would normally take, so as to maintain text alignment.
- Many others are supported too - see site for details.
Pro Open source
Monoid is open source meaning it's freely available to anyone.
Pro Sharpness
Pro Larger and easier to read with thin condensed letters
Pro Fine without retina
Probably the only one that is.
Cons
Con No Cyrillic glyphs
There are no Cyrillic glyphs in Envy Code R which may be an issue for Russian users.

Con Lowercase "w" is distracting
The lowercase "w" is a bit distinct looking due to the narrow nature of the font. This could cause a distraction to some users.
Con Very narrow
Con No bold-italic style
Monoid doesn't offer a style that is both bold and italic.
