The SG bags will not fit on the Kifaru frames, at least not without a lot of modifications.
The EXO bags will fit the Kifaru, though the lid takes a little modification. There are several threads on how to attach the bag on here somewhere. I personally feel the Exo bags are a nice medium between the SG bags and Kifaru.
They speak the truth. I would however say you could attach a SG to Kifaru Frame but it wont attach at the top where you would want it because SG has a different system with their frame then Kifaru.
I am said author of those posts on Rokslide where I crossed the bags on to different frames to test it all out. Kifaru and Exo work well together Just have to swap some buckles out to make it work so that you can attach the Exo bags to the Kifaru Frame.