Since many years I paddle a carbon Celtic Nordkapp cranked paddle.
As a coach my stuff get used a lot in not always friendly ways. Further-on I did a lot off long distancepaddling and multi-day trips.
I do like my Nordkapp blades because for me it's a thrusty powerfull blade. It catches a lot of water what helps to propell yourself and your boat. Gives a lot of support while bracing and also to turn the boat.
After many years intensive use there are almost no signs of wear visible despite use on rocks, shallow water etc. Just some skratches on the surface of the blades.
The crankshaft is that relax to paddle : just hold it with your fingertips, relax your hands and paddle it. For even 100Km or more. In case I need to roll it's just the same: don't worry about the angle, just grab the shaft loosely, perform your roll and the crank will put the blades automatically at the right angle.