I don't think this is that similar to TPN. I understand the comparison — young kids being manipulated by the people they trust — but there's a lot of differences between the stories. TPN is focused on strategy and outmaneuvering your foes, while Shadows is more about the relationship between faces and the shadows they serve.
Moreover, there's no talk of escape in this series like was a constant theme in TPN and this story is more fantastic than the real-word-idealogy-rooyed TPN. The characters are also more grounded (i.e. not geniuses), while the world building is more fleshed out in TPN.
I really love both series, but I get a very different experience reading them. All that being said, really hoping this series doesn't go downhill in the last few arcs like TPN did.