Quality is excellent.
Speed, well, the head is a little slow, but then that's the problem with the entire line of scanners based on this type of design. Personally, I have no problems with the speed.
It can have a little problem with scanning very thick books near the spine where the page is quite some distance from the platen, as the contact LIDE cannot pick up stuff so far away.
Other than that though, I really recommend the Canon NxxxU line of scanners. Can't beat them for the space savings and how they look. Drawing power over USB and using a single cable is a real bonus too.