You've probably already heard "Master and Servant" if you're thinking about picking up this single, so I won't really go into that. What you've got here are that track with 2 remixes: one fairly standard early 80s Depeche Mode remix and an instrumental mix (for you karaoke lovers out there :^)
The b-side, "set me free (remotivate me)", is a pretty cool upbeat track that is fairly consistent with Depeche Mode's early pop material. Checking out the audio samples will give you a pretty good indication of whether or not you like the track.
Overall, there's not a whole lot of material here that would be overly appealing to someone who doesn't already own all of the full-length albums. It's basically a standard Depeche Mode single. Fans, however, will probably want to pick it up for the decent b-side and somewhat less notable remixes.