I took the PCCN 3 years ago, passed and then took the CCRN a month ago and passed. I would say that the CCRN has more resources, and is broader in what is tested. There is just more content to study. PCCN questions are similar to the CCRN but are more focused on cardiac, since there is a few questions on pacemakers, open heart, cardiac, etc. I believe the CCRN to be more difficult for sure, but studying for the PCCN will get you ready for when you have to study for the CCRN. You will have to study for both, no way around that.