It was a decent mystery, but as usually with this type of show you have to accept that the killers are completely insane as it's the only way to justify all of the deaths. A character that's completely insane might as well just be acting completely randomly, so there's no depth to the story.
I really liked the concept of this show. It had a great central mystery that would have kept me interested for another season or two at least, were it not for the dreadful finale. Two significant changes at the end, and both were terrible. So a good show, but skip the last episode.
A decent attempt at a supernatural romance, but it was a little hard to understand at times. The main characters are mostly sympathetic, though not always. Without that connection, there's not a lot of point to a romance-themed show.
This was great science fiction, at least for a few seasons. Unfortunately, the frequent cast changes rendered me indifferent to the fate of the characters. A remake with a more constant cast would do well, I think.
A modern day Jekyll & Hyde story, with one personality being a spy and the other a regular guy. Slater has the charisma to pull off such a role, but unfortunately the show didn't catch on and it was cancelled after about four episodes.