I own both but have only had GZ for less than a week now and haven't really had much time to play it yet.
Immediately I noticed that GZ is much "easier" for me than JP. Like my games last noticeably longer on average and it is far less punishing for bricking shots than JP. In JP I lose balls to the outlane so damn often and it can be super annoying/frustrating. I am not noticing that at all in GZ. Most of my drains have came down the middle.
I'm still learning the GZ ruleset though and have a long way to go. I ended up getting one after playing it while I was up in Galloping Ghosts around Memorial Day and just got hooked.
They are my only pins and they are both great.