I'm not sure exactly what the last poster means, but in any event:
I got the Arca D4 head and the SmartFlex L bracket, both of which work like a dream with the XF camera.
(Kept my Manfrotto 055 legs, though: At a glance, I couldn't find anything comparable from gitzo in terms of weight, height, and functionality) (and for personal reasons, I'm not interested in RRS).
Question for those of you who have the SmartFlex bracket and the XF camera: do you leave it on the camera at all times? I've only had it for a day or so and have mixed feelings about leaving it on: it's certainly more convenient to leave it on, but I'm not liking the feel of vertical handheld shooting with it on. (Not because of the additional weight, which is marginal and negligible, but because it's uncomfortable on my left palm when shooting vertically).