I chose the yn 622 c (2 pairs) not to go especially to TTL because I used to always work in manual either flash or ANP, but why not try it .... so I am happy with the results and I always via the SLR, the possibility to work in manual adjustments and make my way I want on the 1st, 2iem, 3iem ..... flash independently, fine, and soon will release a issuer has put on the PNA and controlling all yn 622 c from the same issuer, because at the moment all this rule on the SLR, too .. Finally the ideal ... Super stuff, I recommend.