My choice to use a birth center and a midwife is based on two things. One, a little over a year ago I switched to seeing a midwife for well-woman care, instead of an OB/GYN, and I found the difference in approach amazing.
And I have heard the birth stories of lots of my friends who have given birth in hospitals and birth centers, and without even hearing all the statistics about how many unnecessary interventions happen in hospitals, I knew that the experiences of my friends in birth centers were the ones that sounded the most pleasant to me. My friends who gave birth in hospitals, for the most part, were happy with it and that was what they wanted, but their stories just sounded way too "wrong" to me--babies being "taken away" right after birth, having to fight with the nurses to get them NOT to give the baby formula, being required to stay in the hospital for a certain number of days, etc. etc.
Some people are more comfortable in a hospital, but a hospital is not a place I'd like to spend any time if I can help it.