Oh this show! So far for the British version, I've only seen the first two episodes of season five and the first episode of season one. Even though I haven't seen too much, it's a really interesting show! I like how it isn't stereotypical vampire/werewolf etc, and I like the characters a lot, especially Alex who I think is really interesting. I found it a little confusing at first since I jumped into the show in the last season, so of course there were some things that tied over, but as of the second episode I think I have almost the complete gist of what's going on! Gotta say, the "Captain" is freaking creepy and I dislike him and I want him to go away. :( But that's to be expected since he seems to be the main antagonist at this point!
As for the American version, I really love it. It always finds new ways to surprise me, especially in the current season where things started off and have continued to be kind of crazy haha! I think the characters in the US version are really awesome as well, and Sally (the ghost of the show) is my favorite. I think this show does a really great job of developing characters, and the subplots are always really interesting!
Only read if you're up to date (on American):