This is a highly original alien invasion story, featuring a (mostly) solid cast and excellent production. Pacing is binge-worthy, although the thrills are rooted in ideas & anticipation rather than high-speed action. There are scattered violent moments, but the main buzz comes from the science geeks, not the fighters. The series is based on the well-known sci-fi books, but be advised: It's not bound by them. Enjoy this TV adaptation for what it is.
If you're skimming the reviews to decide whether it's worth watching, note that many of the 1-star reviews didn't actually review the series. In some cases, the writer gave it 1-star because the series didn't conform to the books; in other much sillier cases, the writer gave it 1-star because the series was cast with the wrong demographics. Those reviews focused on what the writers hoped the series would be, while totally ignoring what the series actually was.