Edd
I also have a J&J, and am very pleased with it, especially for the money. Personally, I have only seen 1 jump cue that I would go to from the J&J jump portion, and that was the X-Jumper, which I have tried out, but it is not made any more, but I made my friend swear that if he ever sells it for any reason, that I get a chance to buy it first.
The 'light' jump cues tend to have accuracy problems, and the 'heavy' jump cues tend to not jump as close, but are more accurate. It took me some getting used to a phenolic tip for jumping, but now I do pretty good with it.
Not as good accuracy wise as my first jump cue, an original 46" Frog, but I can jump closer now. I do like the quick release joint when I need to jump, and I hate to wait on an oppenent unscrewing his if he doesn't have a quick release joint.
Can't you just get a 2 x 4 case that has a separate pocket for a jump butt? I have a 3 x 5, which I think is the right size, but it does have a separate jump butt pocket with its own zipper.
Otherwise, how are you going to carry the jump butt, if you have a playing cue and the BK2 in your case? Even if you had room, with no jump butt pocket, you would need to get a 'foam' dowel cut off to the right size to be under the jump butt going into the sleeve.
Here is the case I ordered for my brother (burgundy at the bottom left):
He likes it, but only plays at home and league once a week, a tournament once or twice a year (He is 65 though):
It is very reasonable, has a jump butt pocket, plus a cell phone pocket, I love the industrial rubber handles, they fit your hand and are comfortable:
http://www.billiardswarehouse.com/cases/action/elite-elcp24.htm