Unfortunately it only gives one version for the USA, whereas my main question is about a variation _within_ the USA.
And only gives RP for GB.
The long O also puzzles me. Take the word No (or know). In Cockney, I hear about three or four vowels strung together. Similar in Aus. Eng., maybe NZ as well. I picture Catherine Tate repeating “I know! I know!” in a sketch, which sounds like “ah nayouw,” or something. (Gotta learn how to do that in IPA.) I’m bovvered.