Commented 5 months ago2019-10-19 04:28:40 UTC in poll: Best Vowel Comment #102350
I Search The Best English Vowel For Research, According To This Link

Mastering the Sounds of English Vowels

"The vowels O, I and A are also among the top seven most used letters in English."
So I Assuming The Vowels "I" Is The Best English Vowel