Only with modification an expensive scrap

The very flexible approach makes this very attractive bicycle. In the same train but it is quite impractical.
For me, I could not use the upper mounting. But the necessary strength was given by leaning on the frame.

The flexible adjustment of the height appears indeed to be quite good, but the screw is very difficult to access the bicycle and dissolves soon.

For this reason, I drilled with a drill with Eisenkopf a hole in the inner tube that's inside the locking screw permanently. Since I have no problems. But drilling is not without its dangers and the necessary material you have to first of all have.

Therefore, in no modification for me just a waste of money.
With a little work you can enjoy a quite ordinary bicycle, I would give then a 4 star, but it is now times not come.