I'm chiming in a little late on the discussion but wanted to add a few things. It sounds as if you've already made your decision but this may cement it in your mind.
My in-laws used to own their own restaurant that was only open for breakfast and lunch. They would have to get up at 4am to get there and get everything ready to open on time. They would normally work until 3 or 4 pm before coming home. Then once they were home there was always work after that they had to do. It was long hours. They also managed it only by themselves which contributed to their long long hours. They always enjoyed it but never took vacations or anything.