I haven't got that exact one, but its basically the same principle.
Obviously they generate a lot of dust, but the main (nontheless obvious) point is you need access to both the front and side, or to mount it on something which moves. The left hand edge of a workbench is ideal as you can use the disc bit by standing round the end. Unfortunately, the unit I have is too heavy to easily twist, nor have I any place to mount it to allow easy access. My (very) limited use of it so far has been on the belt only. Until such time as I have a larger workshop, its kind of wasted on me. A smaller unit might have been more use to me, as I could have picked it up and moved it when I needed it.
Adam