My opinion: the Professional models are great...that is, they are as good or better than Campagnolo NR calipers, which is what they were aimed at. I think "better", but some will say that's a pretty low bar.
Anything less than "Pro" that I've had the misfortune of using have been well beneath the NR bar: Speedys, Equipe, whatever...they are just too flexy and 'cheap' feeling.
I avoid the Modolo sintered pads on all calipers.
YRMV.