Hardware rendering: Yes or no?

[deini]

This is more a curiosity question, but I think that it's also interesting for ROM development/ modding.

I have seen lots of tweaks enabling hardware rendering in most custom ROMs since I have my old HTC Desire.
After a few years; stock ROMs still have it disabled by default (afaik) and most custom roms enable it by build.prop tweaks and also modding a lib file.
I wonder what are the pros and cons of this, and what is the difference between enabling it via ROM tweaks and development options in settings.

 

[redmaner]

It should increase performance in Graphical User Interface GUI.
More fluid/smoother then software rendering.

Mi2/S is already rendering GUI with the GPU (graphical chip / hardware)
Support for GPU rendering was firstly (offically) introduced in Android 4.0 and improved with project butter.
Those HW overlays in developer settings is a part of that.

Older android versions didn't support this by default, that's why they tweaked it in the past and sometimes still do

But this is as far as I know it