The voice answering is a first impression of a business. It is heard ahead of a logo, a website, an estimate. A cheerful tone in a notary office grates; a cold one in a salon does too. And generic synthetic French, at a business from here, grates just as much: callers hear at once that the voice is not from where they are.
In French, the Zenvox voice is a voice from here: a natural Quebec accent, and several voices — female and male — in several styles, from the composed tone a clinic expects to the direct tone a job site expects. Your callers hear someone who talks the way they do, with the words of your trade already in the preset — “job”, “soumission”, “déneigement”. This function lets you hear a preview before publishing a configuration. You hear each voice saying your own sentences, in both reception languages. Choosing happens by listening, rather than by reading a voice name in a list.
The Standard voice mode is the one behind an offer: it is what gets priced, and one Standard call counts as one call. A Premium mode appears in catalogue research, yet what it would consume has been settled by nobody — so it is not offered here, and this page says so rather than selling it.