Oh, it's fast enough. It's definitely fast enough (assuming a decent internet speed). But that doesn't mean it does it well. Even with a language that has few(er) vowels, such as Spanish, it doesn't always hear the words correctly and it'll give you extreme weirdness as a result. All one has to do is look at all the complaints about "Siri" or "Alexa" not recognizing commands. This happens in all languages.