Intense, fast-paced (killer fast!) & dramatic. Flashfall grabbed me from the outset, with such incredibly vivid & unique worldbuilding and characters to die for. Often literally. The world has a grim, dangerous and unstable feel from the first few pages and a death toll to match. And the dystopian elements weren't limited to a corrupt government - there was a real sense that the world itself and everything in it was deadly and out to get you, which I don't think I've seen done in the dystopians I've read before. Certainly not as well or distinctively. 
 What I loved: 
 - The characters. They're believable and relatable, flawed and likeable. Did I mention deaths? Some of them hit harder than I expected. Dram is a perfect tough, ruthless little sweetheart. But I really need to gush a moment about Orion, because she's my new badass girl crush. She's brave and determined and loyal, without coming off as some sort of Tough Girl cliche; her toughness and anger are completely grounded in who she is and the life she's had, and it doesn't make her hard and cold - she still has dreams, she cares deeply about her friends and family and she'll protect anyone who needs protecting. 
 - The action. It didn't let up for a moment. There was never a point where you thought the characters might be safe for a while, or have a chance to regroup. And it managed not to feel repetitive or predictable. 
 - The romance. Alright, it was predictable. Do I care, when it's So Goddamn Adorable? (That's a no, if you weren't sure). And it never overshadowed the story or felt forced. 
 - No infodumps. With a world this new & complex, you might expect at least one, and they're a real pet peeve for me. But the worldbuilding was so skillfully woven into the action, and the dribbles of information were delivered completely in Orion's character. There weren't even any lengthy knowledgeable-character-explains-stuff sessions. 
 What I wasn't so keen on: 
 - Confusion. Alright, I loved the fast-paced action, and the complex world. But by the end if the book Orion had been shoved into so many new places and situations one after the other that I was a bit disorientated. Maybe a tiny bit slower at places would have let me take it in. And the last quarter-ish of the book went so fast it lost some of the vividness I'd loved up to then. 
 - There were one or two points, again towards the end where it felt like Orion was getting too much unexplained outside help, and she maybe wouldn't have made it without. I'm thinking maybe it will be worked out in the second book, and it wasn't so glaring it threw me out of the story - it's more like a nagging itch that just let the conclusion down a little. 
 Overall, loved it. Easily the best read of January, and I'm already looking forward to Flashtide.