Thanks for the great information.The blade is allot more rigged in the Tatara. It also sings a little (not the blade), which is cool i think. You are comparing two really good razors here, so i think it comes down to personal preference. Both are cnc machined, but the tolerances are tighter in the Tatara.
The handle goes into the base plate locking and aligning the blade.
The Nodachi was a little to efficient for daily use. The Masamune was a little to mild. If you buy directly from Tatara i would get the Masamune handle and top cap and the Nodachi base plate.
This configuration is just as efficient as the Lupo, but smoother.
The Lupo gives you more blade feel. The blade flexes a little more. It is as efficient as the Tatara, but feels more aggressive. It also requires a different shaving angle. The optimum cutting angle for the Tatara is around 24 deg. The lupo is probably around 30 deg.
The Lupo is probably a little easier to use.
This combination of Masamune and Nodachi is something that I am considering.