I installed Antergos MATE to play with it and while it was running, I had CPU usage of an Average between 40%-60% on all 4 Cores of my laptop’s i5 430M while just idling. I didn’t continue testing because the usage was so high that I couldn’t even do basic things like add applets to the panels after one. I was able to add one menu applet but it wouldn’t open or allow me to remove the menu. I then tried to add a different menu to the panel but it wouldn’t let me add anything else.
The process that was causing the issue was mostly mate-panel. It was running at 100-120% CPU usage consistently once it started going crazy.
GNOME, at idle, averaged a CPU rate of 1-3% with a maximum 5% across all 4 cores.
Cinnamon, at idle, averaged a CPU rate of 1-4% with a maximum of 7% across all 4 cores.