In my opinion this is the best of the Warhammer 40K RPG GM Kits. The screen contains the most important charts and tables, weapon stats, a summary table of combat actions and rules reminders for different shooting types (automatic, overwatch etc.) and combat against Hordes.
The scenario is the high point of this kit. Without wanting to give things away, it gives the Kill-team a planet as their sandbox and the GM the freedom to run it at the pace and intensity he wishes. Like the best of this kind of scenario, it contains enough structure that the GM will feel comfortable with everything that's going on. The preview on Drivethru should give you a good idea whether this scenario will suit you or not. There's more to this than the scenario in the core rulebook, and it would make a good first scenario for a new Kill-team.
The scenario section also includes some information that it would have been nice to see in the main book - a few paragraphs on day to day life on Watchfortress Erioch and some illustrated NPCs from Erioch. These are the things that help me get a feel for a setting and I'm glad they fitted them in here.
The last section is about how to build good missions and importantly make them different from one another. This will be invaluable to less experienced GMs, but I don't think it hurts to have this kind of material and game-specific examples no matter how long you've ben running games. Given that we seem to have less time to come up with games as we get older, this sort of information is a real timesaver.
I wouldn't normally get a GM screen in PDF, the main reason I did here was because I plan to run Deathwatch online. I don't actually end up using most of the GMs screens I do have though, so that shouldn't really be a factor. I'd thoroughly recommend this product as a solid adventure and some good additional information to supplement the main book.
[5 of 5 Stars!]