The kitchen equivalent of a violin bow, and in the same way a violin may end the orchestra with a single stroke the final cut on your meal should always be done with a single stroke.
The length and sharpness of the Sujihiki knife allow you to finish your dish like the final notes of the orchestra.
The Sujihiki is a double beveled blade whilst the traditional version, the Yanagiba, is single beveled. If you familiar with the use of single beveled blade go with a Yangiba. If not start with the Sujihiki knife as you may find it harder to slice, clean and sharpen a single beveled knife.