Cons - Screws head going to the studs are not strong  enough and lose the threads before going completely in the wall/stud. This makes the whole system prone to fall. 

Another thing is that the top shelf is "Fixed" and so you cant change its height. This was  not advertised and  is a poor design for my needs. 

Parts(wooden) also does not has stickers / identification to help find the part numbers in quick installation.  One can identify this by detailed comparison of one part with other.

pros - Easy to install.