Have you actually seen Austin play? Or just highlights and second hand sources.
I would wait until you see Austin play college level players in a real game. In high school Purvis was much more advanced. Austin was streaker and had a bit of a higher dribble. Neither were PGs, but Purvis had more tools out of the gate. The biggest difference was that Purvis was much more explosive in high school.
Now maybe Austin will transition more smoothly into college but realistically you can't compare until UCONN has Purvis play.