One of the PhD offers is from a new university belonging to a very reputed university system. I like the professors that I met. I haven't met the professor in the other university that's offering me a PhD. It is old and well-established. The location sounds more fun than the first one, which is in a small town in the west. I'd feel bad about rejecting any one of them since they have both been so nice and encouraging. Will that impact my future career and chances of getting a post-doc or job there?