The only thing different about Monaco is it pays well, gets great pacemakers determined to take the field round fast through 1100m and has fantastic weather.
It is childish to claim the track is 'unfair' or 'illegal'. Stupidity beyond reason.
People go there each year and try to run the fastest they possibly can because the great conditions make it possible.
There is NO evidence otherwise. It is embarrassing to sit here and watch grown adults question the legitimacy of sports equipment meticulously tested by various professional, 3rd party laboratories in order to be certified as within the specifications set out by the IAAF for all tracks.
But then the Letsrun experts know it all don't they.
Willis is faster in 2015 than any other year, period. He has had lots of injury trouble in the past and last two years been getting over it and training well. You can shout 'drugs' at the screen also if you like but the fact remains; he ran those times.