The concept of SpeedGrader is good. But the execution is done rather poorly. To begin with, it is very stupid that one has to confirm each annotation and there is no reminder at all if you did not do so. Sometimes I graded half of the assignments and realized that nothing was saved. 

It is a terrible design fault. Since one can easily remove annotation, why one should confirm an annotation by default? I am not even sure it is a deliberate design feature or really just a bug.