I'm using a 5D Mark III and two Yongnuo YN-622C II E-TTL triggers. One is on the camera with 600EX II-RT speedlight on it and the other one is with another manual speedlight.
The problem is that I can't control manual settings of the flash that is on top of the camera. I have to go to the camera settings and change it there. This is especially pain when I photograph moving objects. Every change in power needs to be done on the camera settings not the flash itself.