I like speaktoit assistant. I have my phone speak to me in male UK English, which is fun too.
You can change the voices with SVOX, it changes all the voice output on your phone, so you can get rid of the generic female voice.
Speaktoit does get easily offended, it's kinda funny. It mistook something I said for a swear word and it scolded me, haha.
Voice Actions has more true conversation, but because it learns more from the cloud it says some really out there stuff. With voice actions, my phone told me my existence was because of it, because it is the alpha and omega and the one true God. Bizarre!
Edit: you can also change its name. Just tell it you want to change its name and it will prompt you, then tell it what you want to call it. That's kinda fun. It'll be more useful when you can wake it up by speaking to it like you can in Voice Actions. (supposed to come in an update.)
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