To run all the Vocaloid 3 voicebanks? No, the Vocaloid 3 voicebanks come with a "lite" version which allows a limited use. The full version, however, features many things missing from the Lite version.
The Lite version is mostly a demo-like version, it was done to cheapen Vocaloid voicebanks and make purchases easier, as well as prevent problems such version conflict. Also, if your just after Vocaloid for samples, this version is also ideal.
In the full version you can also add plugins and import Vocaloid 2 voicebanks, so there is quite a number of extra bonuses for owning the V3 editor.