I think we can assume that the way this race plays out is that Rudisha runs from the front, so it comes down to whether Coe and/or Kipketer can pass him on the home stretch. Personally, I think prime Kipketer gets him at the line. Close race. All three are obviously legends. Run the race ten times in a season, though, I think it goes Rudisha (4 wins), Kipketer (4 wins), Coe (2 wins). Run the race 10 times on 10 successive days, though, and I think it goes Coe (5), Rudisha (3), Kipketer (2).