I'm really bored of the Zombie genre and so I held off watching this for a long time. I've just finished it and I have to say I found it really riveting. The first couple of episodes were a bit dull and it took me a while to really get into it, but there are a few things I think it does well.
It provokes an intense sense of anxiety in the watcher, you can really feel the state of fear that those being followed are being forced to perpetually live in. Never being able to rest, nowhere is safe and absolutely no one can be trusted.
Usually Zombie movies/series show people banding together and generally helping each other out. This is largely the total opposite and shows exactly how feral, cruel and self-serving human nature would probably be in an extreme survival situation.
I found it quite a difficult watch sometimes, it's brutal and unflinching and the dark sense of fear and brooding never really gives up.
Perhaps the best thing about it is how some episodes have very little dialogue and don't need it and some of the extended tracking shots are excellent whilst sometimes the camera angles made me feel like I was watching/playing a video gam, which I felt was a good thing due to the enhanced level of immersion.
Yes, the characters sometimes make dumb decisions, but hey, under that amount of extreme stress, I'm pretty sure my thinking wouldn't be entirely rational at all times, so I find that entirely forgivable.
Definitely worth a watch imo.