I tried the CeVIO demo with Sasara, the software has 2 sections (kind of like two different tabs)--one for talk, one for song. I only tried the talk portion, though, I didn't touch the singing. So you can buy either the song or talk voicebanks but you don't need both. I think the "song voice" + "song voice editor" / "talk voice" + "talk editor" must be some sort of key to activate that portion of the CeVIO software (so if you buy another character, you would only need the voice itself and not the editor). If someone could confirm how it works, please do.