Whether or not to use Unity GUI functions

This is a general question. I’m wondering how many people use the built in GUI functions to create their menu’s and other 2D graphical elements in their game, or they create their own GUI elements without things like GUI.box or GUI.button etc. How far can i take the built in gui functions compared to ones i make myself?

Honestly, GUI is so horrible and cumbersome, that you eventually would regret the time you spend on it.
Personally, I find it -way- better to use a secondary camera, and 3d meshes with proper textures for making gui elements. For testing though, guilayout should do.