Decent descriptions, but there's a little more you should know about the three; pickup tone is not based solely on output. You could get a PAF Pro to distort better than a Norton.
Output actually measures very little in the ways of distortion. What it really measures is how easily a pickup will throw a tube amp into overdrive, and how loud one pickup is compared to another.
Let's start with the PAF Pro. I wouldn't call it "overwound PAF tone." It's a very articulate pickup. In the bridge, it's a touch bright, but overall very balanced (moreso than the Mo' Joe imho) and is extremely versatile. It's a very organic pickup that can do just about anything you throw at it. It can scream and wail at ten, but then back off and clean very nicely at clean levels. The PAF Pro is known for a very vowel-like "awwwww" sound, think of a wah pedal left somewhere in the middle. The sound clips on
DiMarzio's website are actually a decent indicator of what this pickup's like.
The Mo' Joe is a very unique pickup. It's got some amazing harmonics up the wazoo, and it's also very calibrated for loads of applications. This and the PAF Pro could be your best options for splitting (although that's not to say the Norton won't split well). If you've ever played a FRED, the FRED's got more sear, while the Mo' Joe has more grunt. It's a very growly pickup, which is much cooler than most people play it off to be.
The Norton is possibly my favorite bridge humbucker. It's rather bright (contrary to popular belief) but still has a lot of low end. It's also got lots of harmonics. I've described it best on the DiMarzio Forum once, lemme dig that up:
"The Norton is, for lack of better description, the bastard child that would occur if a Tone Zone got it on with a FRED. It's got the harmonics of the FRED, but the output and a bit of low-end balls of the Tone Zone. Although, it's a bright pickup overall. It's got the nice midrange crunch needed for good overdrive and distortion, and a very distinctly PAF aftertaste."
And I personally wouldn't compare a Norton to a JB, two different pickups altogether. I've also heard that the Norton nails the Brown Sound, although I disagree with that as well; the Norton is it's own beast.