I can't say for sure because I've only had the one group, so I can't compare. The fact that they're are so few big ones for sale or vids of them to me suggest they're just as fragile as ever but again that's just conjecture on my part.
Still IMO they're worth the effort. Jacks have always had a spot in my heart since they where one of my first fish. So when you combine that with the EBJD's amazing looks, they become irresistible to me.