The difference is that the Cataract oar is a filament wound procedure over a mandrel which is pulled out after the resin is cured and the blade is plastic. The Sawyer is a triaxial braided fiberglass/aramid fabric (woven like Chinese finger torture, remember as a kid?) and is laid up over a shaft which remains as part of the oar. The difference in performance is huge with the Sawyer being probably 30% stronger and 40% more flexible which was the whole idea behind the desing and lay-up schedule. Add a ferrule? You give back about 15% of the flex.