I totally recommend this set of adventures to anyone. I've been running this campaign for a few weeks already, and I think it has grasped the interest of my gaming group very well. The setting is interesting and well built, go for it.
Now, here are the things that I needed to change from the original text for my home game; they work for me, they might not work for you, just use them as you see fit:
- We live in Barcelona, Spain, so I've changed the ocean for the Mediterranean, and I'm running this show in a familiar environment for my players: the catalan coast. Again, this is totally up to you (and yes, zombies work really well in Europe too, watch the movies 28 days later or Rec), but I'd totally move the events of this campaign closer to where you live for a much potent dramatic effect.
- I've changed the names of Cap. Romero or Kirkman. They give away part of the story. When we started playing this, I didn't tell the guys that this was a zombie game. The look on their faces when they met the undead for the first time was worth the trouble!
-Finally, the plot is waaay too railroaded. If you're not careful, your players will be reacting to the events set by NPCs, and following all the choices made by those NPCs. By al means, don't do that... in fact, you don't need to! You don't need Kirkman stitched to the PCs trousers all day, so let them run for themselves (in the begging they're trapped in a boat, they are not going anywhere!)
Anyway, this a solid plotline, with lots of potential fun for you and your gaming group. Many weeks of gaming for just 20$ is a steal.