The lamp sits well and is very steady. It lights up my whole screen and doesn't leave any parts unreadable even if the room is pitch black. But I've only used it a couple of hours and the lamp has already started to flicker sometimes. It'll stop if I give it a carful bump but that's the reason I only gave it three stars. Could be that the batteries that came with it weren't good or something.
Edit: Changing my rating from 3 to 5 stars. The flickering thing was only happening because the battery was loose and had to be pushed properly into position. Haven't had any problems with it after that.