Ahh mate I spent ages last night looking for it in the forum classifieds................ I faiiled to find it so I thought it had sold... literally in the last half hour II have just pulled the trigger on a used mint flexshooter pro I found on line.........
On the assumption that the Flexshooter works the same way as the Uniqball. which, In spite of the differences, as they were both designed by the same people, I suspect they will I have a tip that might save you a lot of frustration.
Although the construction of the head is described in terms of an inner ball and an outer ball, the "inner" ball works like a pan and tilt head, not a ball head. With the outer ball working like a levelling base for this pan and tilt head. Although this is actually obvious, until I got used to it, I found I kept on expecting the "inner ball" to work like a ball head, which it doesn't and can't..
There are a few others things that you need to "learn" about using these heads, as when you are using them for general use (as opposed to a gimbal substitute) you often end up needing to combine adjusting the outer and inner balls in an iterative manner to find the right position. This can be massively frustrating, if lose sight of the inner being a pan and tilt head, and that you aren't simply trying to manipulate two ball heads.
A third issue, which may not be the same with the Flexshooter, in spite of the levelling ball + Pan and tilt ball approach, the Uniqballs don't work as pano heads because the panning axis is in the wrong plane. This has the weird effect of while keeping the horizon horizontal when you pan, it allows the level horizon to move vertically within the frame.
You don't notice this when panning a flying bird, because relative to the bird the horizon stays level, but you do notice it, if you are trying making multiple images to stitch together as a pano.
This may or may not be helpful, but just in case it might be, I thought it worth mentioning, as I found both my uniqballs took a bit of time to get used to.