I have bad luck with self-assembly in general, but these didn't go together perfectly for sure.  I bought two and I use them anyway, they look great and have no functional problems, but in both stools 2 of the upper screws had to be abandoned because there was too much space between the back and the base, and it one stool the bottom rung only lined up 3/4 screws.  The other one wobbled but I glued a button to the bottom of one leg and now it's solid.

Still totally usable and sturdy, and I bought on clearance so that might explain the imperfections.