Hi Deadpixel....
I'm still considering between the SHarpa PRO CF640(John 3:16) or the Mamiya AY702.. So far, I'm leaning towards the Mamiya tripod, but no idea about the head yet.... $500 seems quite a lot for me on the head...
I've got the Sharpa Pro CF640 and am very happy with it. I usually avoid tripods with 4-section legs because they tend to be less stable but I must say that this one is really, really stable and since the leges get reduced to 4 sections , it collespes down to a pretty small package.
One thing that often irritates me about tripods/monopods with twist-nut tightening mechanisms is that the legs tend to rotate as you twist the nut, making it hard for you to properly tighten the legs. Velbon has overcome this so that you do not face this issue when tightening the nuts.
As for the head, you'll have to consider whether this would be the only head you're getting or if you'll see yourself upgrading to heavier equipment and better heads in the future. If you have plans to upgrade, you'd be better off biting the bullet and getting a good head right off.
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