If you'd ask me I'd choose Daniel without much thinking, his drawings feel alive and those are the kind you want to transmit emotions through images.

Now, of course with what we're seeing here, both artist are not in fair conditions, we have a full double page Inked by Daniel, and just some characters in standard generic poses by Gian.

If you really are undecided, pay both to make a single frame/scene fully coloured, where you can see emotion, action and ambience.

That should give you a real preview of what you would be getting.
It's important that this trial is a paid one, as both artists would be investing their time in doing the best they can do.

Just my two cents 😉