A couple of my friends did it and whilst they did enjoy it, they seemed to have a fair amount to do. Particularly in the first year, the course does encompass a lot of aspects e.g. one of the big modules involved a lot of study of the physical brain, anatomy and such. Statistics also played a part, as well as experiment design and other "practical" applications of psychology and its use.
That said, they did say they find it interesting even if aspects of it could be hard. (Pretty much like any course really)