The seat is actually very easy to assemble, no problems there. We checked again after, shaking slightly at the headquarters, attracts possibly again slightly, fits.
To complain, we have that the Patent with the buckle is not necessarily the best solution. I'm just waiting until I am einzwickie times coarser when closing wait. In addition, the belts are very easy to draw firmer, loosening (eg because the child wears a thicker jacket and you have to adjust the strap) only works very unsatisfactory.
The seat is insgesam okay, but we had expected and more.