Very sturdy and pretty simple to put together. The instructions are so cute, they manufacturer incorporates little jokes into the instructions to make the assembly process more fun. 
My only problem is that there is a little gap in one of the legs of the bookcase. I thought it just needed a little weight and the gap would close... but no luck there. The gap doesn’t run the structural stability but it is just something I noticed and it’s annoying  it   didn’t sit perfectly. 
Overall, would recommend because it isn’t too noticeable and I think it’s just a glitch with my bookcase but not all.