I originally found Di Prato's via Yelp when we were new to the Columbia area. It is close the USC campus in a very nice location.
My wife and I have been here on a few lunch dates and even brought in family visiting from out of town here.
They have a great menu. The other reviews cover it all. The panini's were "as good as it gets!" and their mayo+pesto sauce creation is amazing.
It wasn't very kid friendly as it is usually very busy. I have felt that it was a little "stuffy" there depending what day of the week you go.
Always a great take-out option!