I gave it 9 stars, although it probably deserves more like 8, but I felt that I had to do my part to upgrade the rating a little.
Some parts of the story are absolutely ridiculous and farfetched, the computer generated scenes of the football matches were some of the worst I've seen in recent memory, however I was entertained the entire series and I definitely want to see the second season.
The two leads were both terrific and elevated the show beyond trashy camp.
It feels a little bit like watching the over the top and absurd Boondock Saints at times crossed with a really good English serial... however the portrayal of the central characters somehow lend credibility to the proceedings even when the plot veers way off the rails.
As an American it's hard to tell where this series stands in comparison to other German television shows, and it's difficult to judge what aspects of Berlin life and culture even remotely resembled reality. I did find it fascinating, however and it made me want to try other German series.