Re: Which of these pickup sets.....
A Distortion with an Alcino V magnet *is* the JB. That said, the JB is really a bridge pickup and not recommended for the neck position. In my experience, a JB can sound great in some guitars and horrible in others. In an alder bodied strat, it tends to sound harsh and lacks in bass.
I would go with the Custom Custom in the bridge and the Distortion w/ an Alcino II in the neck. The Custom Custom will really fatten up the bridge although I have no experience with a Distortion w/ an Alcino II magnet.