For me, anytime a scientist says millions or billions of years, it's because they can't show it happening in a reasonable time frame. Personally, I'm not a fan of taking sides at this point. I can see value in the concept of reason, and I can see value in the concept of God. Either way, we're still in the here and the now, and debating the origin of life, while occasionally an enjoyable exercise, isn't something that's going to to be figured out by any of us. Using science is like trying to prop yourself up with a crutch that never quite reaches the ground. There are always going to be more questions that follow whatever questions you answer. Faith is a crutch that will actually reach the ground, but only from your specific perspective. The others around you might still see a guy flailing around on the ground.