I have issues with it and now I have to do a DFU restore to get me back.
Initially, I had issues with AppSync and how it crashed some stock apps like Mail, Safari, Weather, Notes, etc. I found a way to stop the crashes.
I also noticed my signal strength indicator (I have it in dB) that it is very slow in switching cell towers.
Random crashes of other apps like Heywire. I went to and tried to view a youtube video that was linked in Cydia and my device became almost completely unresponsive. I got a black screen but Siri and reboot worked.
I dunno if the Pangu JB caused ALL of this or if somehow Appsync did, but I only installed a few apps through Appsync like iFile, Shazam Encore,and iCleaner. With iCleaner, I left things at the default setting and didn't tinker with the settings.