When comparing 6x13 fixed vs Hasklig, the Slant community recommends Hasklig for most people. In the question“What are the best programming fonts?” Hasklig is ranked 28th while 6x13 fixed is ranked 37th.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Well designed
6x13 fixed is the apex of bitmap fonts. It has a nice, defined character set and great proportions for quantity of text onscreen, making for excellent readability. It is aesthetically pleasing for a bitmap font and has been deservedly termed 'classic'.
Pro Legible at small sizes
At a small text size, each character has a limited resolution. A character size of 6x13 pixels means only 78 pixels per character. Modern fonts are designed to be scalable and are less legible at these small sizes. Using bitmap fonts increases legibility by eliminating scaling and sub-pixel aliasing artifacts. Some scalable fonts include "ppems" embedded bitmaps for this reason.
Pro Available on every X server
6x13 is the classic fixed monospace bitmap font that is expected to be available on every X server. It is part of the misc-fixed family. These fonts were handcrafted for readability in a terminal.
Pro Widely available
It is distributed alongside the X Window System.
Pro Great for Haskell
Pro Has a heavier appearance than Fira Code or Monoid
Pro Completely free and open source
Freely available via GitHub, therefore can be modified and improved by anyone.
Pro Has many variants such as Italic, Bold Italic, Light, Semibold, etc., etc
Cons
Con Doesn't have a slashed zero
The absence of non-slashed zeroes makes it harder to distinguish "0" from the letter "O".
Con Extremely small on high-DPI screens
While it is crafted for a screen where the pixels are visible, bitmap fonts do not work well on high-DPI screens as they do not scale too well.
Con Lacks !=
Some coding fonts with ligatures, like Fira Code, turn != into ≠, but Hasklig does not. The reason for this is that Hasklig was designed for Haskell code, and so turns /= into ≠ instead.
Con Some Ligatures like -<< don't look that good.
Con Has a heavier appearance than Fira Code or Monoid
Con No support for many editors, including emacs
Unfortunately, not supporting emacs is the number one reason I don't use this font all the time.
Con Very cute but not WYSIWYG
You want to see exactly what you've typed, not have your brain have to do a little dance every time you see one of these artifacts.