This is difficult, as who I
think will win is not necessarily who I
want to win!
I think Gareth will win, with Will second, Zoe third and Darius fourth.
However, I would like Will to win, with Darius second, Gareth third and Zoe fourth.
I agree that Gareth's voice is better suited to 'pop' music, so that's probably why he'll win. However I think Will is the one with the special talent, who will ultimately have the most successful and varied career.
All four should, without question, be offered recording contracts, and I hope that they all go on to enjoy great success - they deserve it.