Well, here's how I look at it :

"God theory": I don't understand it, so some greater being did it.

Darwin theory: Here's what I observe to be true on X scale, you can amplify it and apply it over a time period and that explains unobservable results.

The latter of course doesn't encompass the more important question of "why". It explains how it works, but of course doesn't explain why it works that way, as opposed to working another way, or whether or not there are other factors involved. That's the fundamental flaw with the perception of science. Its explaining an observation - assuming that if the explanation is reproducible that the understanding is complete. In essence science is the reverse engineering of our world. When I say, "its just a theory", its because science is far more nebulous and interpretable than logical systems. We're working with a black box, trying to understand what's in that box through deduction and experimentation. It will always be a fluid process, with our understanding subtly changing over time as we refine and adapt it to meet new observations.

Realistically we may never have the full understanding of the topic. So basically I look at the Darwin theory as "good start, needs work". But if you asked me if I "believed it", I'd say "what's to believe?" There are two parts of the Darwin theory :

1) Readily observable facts. IE - genes, reproduction passing genes, etc.

These don't require any belief - they're readily observable. This part is pretty much set in stone.

2) Unobservable assumptions. IE - the human eye is the result of many different mutations over the span of many many years.

These are the ones that require a "leap of faith", and I think its fair to say we're probably wrong here to some degree or another, or aren't accounting for something. That's a pretty defacto presumption of mine when we're making guesses rather than direct observations