Yes it was, Quartey has one of my favorite jabs of all time.

Anyways, I would definitely consider Cotto's jab among the best which is amazing because I never saw the jab as a primary weapon until the Quintana fight. I think this goes to show how great of a fighter Cotto was. A lot of people with his type of power stop improving, Cotto has been improving ALL THE TIME and constantly tightening his defense and developing that jab which he cemented as one of the best in the Mosley bout.

And like you said, he might have P4P one of the more forceful and hard jabs in the business.
In no particular order and off my head I'd say the best current jabs in boxing belong to these bunch.

Wlad, Wright, Kessler, Mayweather, Rafael Marquez, Nonito, Cotto and Cunningham.

Other guys like Lamont Peterson, AJ Banal and Andre Ward have very good jabs but aren't at that level yet.