I haven't watched it yet, but I voted Nicola for the sheer drama she could bring.
Speidi always seemed too manufactured to me, all of the "are they playing a game? are they not playing a game?" nonsense that Brian and Emma went on about during their series got on my nerves. Yes, they are playing a game and you are an idiot if you can't see that. Everything they do is for the cameras. I don't dislike them though.
I seem to remember Austin as being quite petulant and aggressive, though I don't really remember too much of the details.
Colleen and Callum both seem like very nice people, but a bit bland.
I do like James, he puts on a performance but unlike Speidi it feels like it is for his own entertainment rather than ours.
Edit: I forgot to mention Jasmine, which just about sums up what I have to say about her. Is this they best they could come up with? Nothing against her, but there are an awful lot of people I would have chosen over her.
I'm glad that nobody from the most recent Summer series returned as I didn't watch it, and i'll turn this one off too if it gets too manipulated