There is a bug with glyph rendering on OS X. For example, when using a dark theme and Monaco font at 12pt, the "n" letter often looks cut off at the right side:
This sometimes happens with other letters, too (I've seen d getting cut off, m looks a bit weird in the example). Terminal and TextEdit (and I think everything else) render the letter just fine, so it must be a ST2 problem:
Please fix this, it's very annoying to look at.