I'd already purchased the first three when this came out, but I got it anyway. There are five discs for four series, with series four comprising two discs, but really, the only thing I can see different is the box; there are no bonuses, unless you count the box.
Series one and two flow into each other quite well with recurring characters such as the yelling promoters of Utoxeter (Daaaaamn!!!) and Tony and Control of MI5, but it seems Fry and Laurie had not expected to continue on to three and four, and so came up with conclusions for many of their regular sketches. Holding this thought, series three has a very different air. For instance, there are more musical segments (like my favorite "Kickin' Ass"), and Mr Music playing out each episode while Stephen Fry mixed a strange (often frightening) concoction. I thought they had found their groove in this series... Only to lose it in series four.
Word is that the series was moved to BBC1, and Fry and Laurie lost much of their creative freedoms. For example, they now had guest stars, such as Caroline Quentin (Men Behaving Badly) and Robert Daws (Jeeves and Wooster), who didn't really play any vital roles. Hugh Laurie did a musical segment in each episode, all of which were wonderful and helped the series like a crutch. While series four was awkward, it still had its moments (usually having nothing to do with the guest stars). Why seven episodes had to be broken into two discs, I don't know.
While series one and two were united by recurring characters, series three and four were connected by Mr Music. But what made this programme "A Bit of Fry and Laurie" (besides Stephen Fry and Hugh Laurie, duh) were the vox pops between sketches.
This is definitely a must-have for fans of Fry and Laurie.