The XPO has standards that pivot in the middle. A heavy lens may balance easier with a center pivot. This is mostly a personal preference with a wood field camera. In addition this style may give your more movements than with a bottom movement standard. Again it may be more than you need. The HCZ will fold up into a box, with the lens removed and protects the camera body for transport. I rarely use this so again feel its not all that important.
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