It's a shame that the boxsets are so badly made (apart from my season 1 set, which comes in volumes which are all encased in a cardboard sleeve).

They are made out of flimsy plastic, several of which are broken already and/or do not close properly, and there isn't an episode guide included within, so if there is a particular episode I want to watch, I have to guess which disc it is on, as they are not necessarily in the same order as the official episode guide on Wikipedia either. :(