Short review: Meh. Might be ok if you pretend this is "ultimate" version of the Teen Titans.
Longer review: Not really the Teen Titans but the story was ok. Lots of characterization problems (IMO, really got Dick and Kori wrong. Donna Troy was off as well). Felt like they pulled the "this is a dream/happening only in someone's imagination"card way too often.
The best written episodes were by Geoff Johns - and those were the only ones that had solid characterization. Ever other episode missed the boat.
My god...the body count on this series was crazy - we're talking Punisher level violence.
Overall it felt like the writing staff (with the exception of Johns) doesn't know these characters and were told to be as dark and gritty as possible for some reason. Which doesn't really work for these characters, imo.