Comment 25 for bug 164640

There are numerous problems with system cairo 1.4.10 compared to patched mozilla cairo 1.5.2-55.
1st, system cairo has tons of fatal asserts, making firefox crash in different locations with ugly messages. Mozilla turned asserts non-fatal as they deal with errors they think important and ignore the rest.
2nd, mozilla fixed a number of issues (performance, glyphs, bad repaints, printing issues, etc), some (most?) merged into system 1.5.*.

From a user perspective, system 1.4.10 will appear somewhat slower and will have more visual artifacts, not to mention that the associated bugs will not be supported by mozilla.
You are requesting improvements for subpixel, yet the patch decreases overall quality for everyone. That's a 6+ months regression of mozilla improvements/bug fixes.

It would be better to have that subpixel patch accepted upstream by cairo, or at least by mozilla.
Or hardy could ship a patched 1.5.* (I don't know if it's even possible).