I once came across the idiom "bar none" for "by far/with no exceptions" as in "He's bar none the best player on the team", after what (for some reason unbeknownst to my forty three year old self) it was forgotten and fell into oblivion…until just recently, as I came to rediscover it sometime earlier today searching the Net for some other expression I previously posted about.
And so, I wish someone would tell me whether this idiom is acceptable for all English registers, or definitely belongs to informal, colloquial usage and, as such, should be best avoided in formal style.
e.g.
Bill is bar none the most talented photographer…
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Best Answer
It would be acceptable any place that idioms are usually acceptable, which is to say it is slightly informal but not very informal. It would be ok in magazine writing -- think Slate or Rolling Stone -- but not in academic writing, hard news (i.e., newspaper articles reporting news), and the like.