Hi J.-
I delivered at Good Sam two and a half years ago. I ended up in the hospital a week before delivery due to complications and had my daughter one month early. Am I glad I was at Good Sam! It is a no frills hospital, no cushy rooms, fancy food, etc., but as far as care goes, I feel that I got the best. The nurses and doctors took great care of me during my stay and they took very good care of my daughter once she was born. I was also comforted by the fact that they have one of the best NICU's in the country as part of their facility. I didn't need to use it, but it sure was nice to know that it was there in case we did.
I don't know much about St. Joe's except that my youngest brother was air evacuated from Prescott to St. Joe's back in the early 70's and they saved his life. I have never heard anything bad about the hospital. It may be stellar as well.
All I can do is tell you from personal experience, that the care at Good Sam is superb!
Good luck in your decision making and with your delivery.