M.R.
I really think it is a matter of personal preference, how you imagine your childbirth and preventative routine medical care should be, and how you feel about having a male or female caregiver. Depending on how you envision your care plan to go, there are pros and cons for both.
I chose to go with an ob/gyn and never considered (nor would I consider) a midwife. For me, it is a matter of personal preference. I also have some intricate health issues that I feel are better addressed by an ob/gyn. I hope people don't buy in to the unfair generalization that ALL ob/gyns are evilly-grinning, scalpel-wielding surgeons just DYING to cut your baby out of your belly despite your protests. Believe it or not, there are several caring and knowledgeable ob/gyns out there who really and truly listen to their patients and honor their respects and wishes. I should know; my solo practitioner physician is one of them. Since he is the only doctor in the practice, he is the only one I see and I was guaranteed that he would be present for the delivery my baby (although...after 3 hours of pushing, he decided to give me a break to rest and stepped out for a minute...I'm not even kidding when I say that 5 minutes later my child came out...so technically it wasn't a 'guarantee' that he'd be there, but it wasn't like he wasn't there because it wasn't his night to be 'on call').
Some women are uncomfortable with male ob/gyns and that is completely understandable. At the end of the day, you need to make a decision that you will feel good about and you should not be criticized if you choose one over the other. Good luck with your decision!