Zoo

I was wondering how Italians pronounce the term zoo: is it ˈdzɔo or dzɔ? If you look this word up in a dictionary such as Lo Zingarelli (2007) or Il Devoto-Oli (2011), the only pronunciation they give is ˈdzɔo. I assume this is because they are rather prescriptive dictionaries. But I don't say ˈdzɔo. I say dzɔ. And I'm not the only one: my parents, brothers, grandmother, aunt all say dzɔ. Are we all wrong then?

The only dictionary I have been able to find which also provides the variant I use is the Dizionario di Pronuncia Italiana (DiPl, 2009) by Luciano Canepàri. The author considers ˈdzɔo as the main pronunciation (by which he means that that is the correct one) and regards dzɔ as frequent but slipshod, highlighting that it should be avoided as it may indicate that the speaker is not well educated.
I don't regard myself as uneducated at all! My parents and my brothers aren't either! So which form do you think you mostly use? Which form do you prefer? Would you consider a speaker uneducated if they used the variant I do?

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