( saying ) used to say that there is not much real difference between two possible choices
IT'S SIX OF ONE AND HALF A DOZEN OF THE OTHER
Meaning of IT'S SIX OF ONE AND HALF A DOZEN OF THE OTHER in English
Oxford Advanced Learner's English Dictionary. Оксфордский английский словарь для изучающик язык на продвинутом уровне. 2005