Excellent machined, great finish, precise threads. But... fine threads (M30×1 for ø 32 columns, M20×1 for ø 22) take skill to connect and especially the large ones could do with a cylindrical part in front of the thread to get the center quicker and safer. Just like the smaller tubes already are designed with. And I also wonder, if double threads would have been much less solid? Anyway, the system is great, it just takes time, patience and steady hands to connect the extension tubes. The ø 22 are faster to connect than the ø 32 (only 11 instead of 15 full turns). Stability is great anyways.
And please, rogeti, a better description of what the extensions are made for would be very helpful.
Was worried this wouldn't hold up but so far I haven't had any issues using it with a long lens and a medium format camera.
Bought it for use with the t adapter for horizontal shots, however it also is good as an under weight for the center column to keep the tripod steady.
No flex in the tube, well built, using with the T adapter and a GFX 100II