Sorry Brad, don't know anything about the Carbonprene.
I have been using Picasso Carbon fins for over 2 years and think they are a great fin. They are a stiff fin, stiffer then C4 40's, way way stiffer then the new Omer Carbons. Part of the reason is that the picasso's aren't tapered like the other 2 fins, which makes them feel a lot stiffer at the tail. Maybe the Omer carbons you saw were the old style which weren't tapered either ?
I have used the new Omer Carbons and found them way too soft for my liking, they snap easy too.
They do seem efficient, so would suit someone wanting a soft to medium stiffness fin. Most of the Australian team were using these in the Pacific cup.
Cheers,
Wal
