So here's my 2 cents for what it's worth. First off what r u looking to do with the ski if u want one to go all powder and like 5% groomer the the bubba is gonna be your best choice. But if u want to be able to do anything besides powder the JJ is gonna be your best choice and it is actually a good all Mtn powder ski so it rides just as well on days that aren't pow. The magic j is just a wider version of the jj it is through a little squirrelly on the hardback then the jj is. Hopefully this helps.
Unless you get to ski a foot fresh everyday your skiing or are crushing big mountain lines, I would choose the JJ. You can ride a JJ every single day and have no issues with condtions