. You've got a high quality imaging system and it would be a shame to compromise image quality with a ballhead that doesn't securely support your camera and lenses.
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From my experience, it's pay now or pay more later. With the quality of your camera system, at a minimum I would start with an "top quality" "L" bracket, RRS, Kirk, etc, then a compatible quick release clamp (I like lever) and then the ball-head (which you may decide to upgrade later as budget permits.) The error, that I made (I not paying that much for tripos stuff, ignorance) is that I now have a box full of "second line" incompatible clamps, plates, etc) If I had picked a first line plate and clamp system at the start and then planned on upgrading head and legs later, I would have saved money.
Steve