When comparing Courier vs KaiTi, the Slant community recommends Courier for most people. In the question“What are the best programming fonts?” Courier is ranked 52nd while KaiTi is ranked 97th.
Ranked in these QuestionsQuestion Ranking
Pro Clear glyph resolution
Pro Simple yet effective
Pro Comes pre-installed on almost any operating system
This means that the user doesn't have to go to the bother of installing anything.
Pro Very clear even at small sizes
This font is included in windows by default and is really easy to read at small sizes, allowing you to keep more code on the screen. It was originally designed for simplified Chinese.
Con No differentiation between 0O and Il
Zero O and cap-I lower-l look the same