Pros:
Call me a sucker for video game based themes but you've got to admit the quality of game based themes is usually second to none. The graphics are computer generated so you don't have to worry about poor scans or highly pixilated images. The sounds are all short sound effects that do not become redundant like those one liners in most movie-based themes. Rotating 3D cursors are often a standard part of a great game based theme and icons are usually perfect cutouts. Better ones even include a screen saver. With all this in mind, it's safe to say that Pedle Zelnip's Doom theme is one of the "better ones". Doom gaming fans will love it.

Cons:
Fixed!

Overall:
Love it when theme authors upgrade for the better!