I'm a past-CC user for the most part, and others will be able to give more insight into its virtues, but I see the differences/advantages mostly as this: CC is in essence a CAD program, so you have a lot of scale/zoom/exactness type power when you use it, but it lacks some of the artsy filter-type stuff you can get using PS. That said, we have several users who make stunning maps using it. Also, my experience is with CC2, and as I understand it they've added some of the artsiness into CC3 that was missing before.