Just upgraded my '14 Cherokee with the new 8.4 system from the basic 5.0 that had no sirius/xm, back up camera, etc. Bought the 8.4 system on eBay (very hesitant at first) but turned out it was completely plug n play and worked great! The listing on eBay said it was just the basic 8.4 ra3 system with no nav but when I installed it, the nav option happened to be on there and works just great! Awesome surprise! Saved some money too. Now I just need to buy the antenna for it which shouldn't be too expensive. This system is 100x better than the 5.0. Definitely recommend doing this upgrade if you are interested.
I think I was the guinea pig on this forum and did this first. It is by far my favorite mod. I'm glad your's worked for you.