My point with the 'You say tomato - I say tomato' quote is that I feel that there shouldn't be a 'correct' pronunciation. During the last century there was a strong drive in the UK to eliminate regional variations in pronunciation which fortunately failed. The UK would have been a poorer place had it succeeded.
I was born in the south east and have a Thames valley accent, my wife is a northern lass from Yorkshire. We pronounce many common words differently (I use the long a, my wife a short one, I call certain water fowl dux, my wife doox,) Fifty years ago my accent was 'correct', I defy anyone to say that now. As in all things 'Vive la difference!'
The only criteria that is important is that we should be understood.