Dont get this urge for people to have their towers on the desk!!!!
Up until recently I'd always had the same view but I wanted a way to easily check my water loop wasn't leaking or needing topping up and after trying and failing to get a fill level sensor working I thought I'd give it a go.
One thing that always put me off was my perception that the system would be louder on the desk than under/next to it but running my fans around 800rpm it's barely audible from 2 foot away.
Obviously it works best if your case has a window/lighting etc but I really like it and as others have said it definitely makes a difference to dust build up.