I was very impressed that someone had thought of this when this map pack was first mentioned. Finally having suitable maps to do one of those creepy "inside massive villan's body" levels that crop up in so many videogames seemed like a great idea. On getting them I was a little disapointed at the final result's lack of internal detail on some of the creatures.
That said, the sheer intimidation value these maps carry when my player's know I've got them along with me is easily worth the cash I spent on them.
I feel I must first point out that this doesn't seem to be the sort of rpg aimed at rules lawyers or players wanting to be 100% in character and 100% serious all of the time (no offence intended).
It's aimed at players who are playing for fun and it succeeds like no rpg I've ever previously played has before. The rules are simple to learn, easy to customize and have plenty of interesting ideas, and the background is the sort of entertaining weirdness I've grown to expect from the DG crew.
The DVD was both an interesting extra and a very effective way to indroduce newbies to the setting.