How far away would you accept a preschool to be from your house?

My son's current preschool is 2 mrt stops away from my place. I take the train with him every morning to bring him to school before I go to work. It takes around 30 mins and we use this time to catch up, bond and talk. He really loves the school, his teachers and friends and I've seen how much he has grown in the school. I have many other schools that's one bus stop away only but they weren't on my list of choices then. To me, location wasn't my top priority when I was looking for a school. I guess it depends on what you can work with and how much priority you place on your deciding factors of the right school for your child.