I'm not sure if I'm repeating myself or am thinking of another forum...
What was the flying condition and test conditions for the high speed data on the He100D? Is it calculated data? Is it for the one minute limited maximum emergency setting of the DB601Aa, after which the radiator would be lowered? What was its performance with the radiator extended at the steig/kampfleistung setting?
When the He112 was flown comparatively against the early 109 (both Jumo engine versions) it was shown that fitted with combat gear the 109 was better and the evaporative cooling system may not have been combat worthy. I would presume this was a similar situation with the He113/100. Its high speed condition is most likely very limited, where in the medium performance range and in extended combat the 109 probably performed equally, better, or similarly.
My personal assumption has been the He100D may have had a better high speed run but it was limited, whilst during extended high performance scenarios it lost any serious advantages for the bulk of the mission, at the cost of a more complicated, specialised and expensive production. Due to the success of the 108 the 109 (which shared some initial tooling) was very easy to place into mass production quickly, almost contradictory to this it also performed admirably for the time and was very popular with pilots.
He100 was probably a better racing plane. 109 a better ubiquitous fighter, I'm guessing.