I have 30 of their 6 foot shelves and had NO problem hanging or connecting them. Eric's Trains made a video, which is on their website Episode 42 (https://www.youtube.com/watch?v=XvqTGwLqOeI), showing how to spread the pins and hang them. As for quality I have no complaints. Unfortunately most of us think we know and refuse to look at the instructions. I actually hung my shelves then put the pins on. I then used a block of wood on the end of the section I am adding and tapped it on. NO PROBLEMS !