So I too will be getting a Gitzo soon, specifically the Gitzo Series 5 Systematic 6x Giant, which does not come with a center column as is. You can order a center column to fit into the tripod, hence systematic.
I do not like geared columns, and will be getting the rapid center column. I would prefer the short center column that Gitzo makes, but the only pictures that I have found of it are of just the center column. Meaning that the images show the center column without the locking clamp (which is shown on the normal length rapid column) that holds the center column in place. This piece is also the piece that attaches to the tripod: without it, you can not use the center column.
I have not been able to find any definite answer to whether the short column comes with the clamp, or if you need to order the normal length as well in order to be able to use the short one, or if you can order the clamp by itself.
Does anyone have the answer to this?