No assembling needed. This one comes as pictured with screws.
Looks very nice, feels solid.
The only thing that bothered me a little is that the angle of the metal rails starts already at the bottem. I was planning on having a 4U piece of gear at the bottom, but that leaves a space below. So if you have a unit that's 2 high or more and deeper then, say 20 cm, you'll need to put a blind plate below (or not). But I'd say it's rather a 20U piece of furniture instead of 21.