lkjy improved the original list I suggested. Please keep in mind that when you suggest the best milers of ALL TIME we need to keep in mind all of the advancements made in medicine, facilities, and etc. We should not merely go by the times athletes have attained. Olympic Gold medals are only one measure because opportunities are greater now than then because careers are longer.
If you got hurt in from 1920-1980 chances are you were done.
Here is lkjy's suggestion:
1. Hicham El Guerrouj WR in mile for 9 years now
2. Sebastian Coe 2 X Olympic Champ
3. Kip Keino African Pioneer
4. Jim Ryun Mainly for what might have been as he peaked at 21
5. Herb Elliott Never beaten over 1500/Mile and retired at 23
I'm going to add an Honorable Mention which could be fun to debate.
HM goes to Roger Bannister because he ran under 4 minutes in 1954 while mostly running less than 10 miles per week and that only in season!!!
He had incredible talent!