I have been pointing out you just need a good airflow, not great. Not sure why others doesn't get it.
Anyway, Gamer Nexus also has a review for H200 about negative airflow and with sfx psu that gives better gpu temp. But on my own experience it is not. When playing games 100% gpu load the hot air got stuck somewhere at the front. This makes the TG side panel very hot to touch. Installing 2 front intakes significantly improve the airflow.
I think it's going to be the same for H510 (which is H500 basically).
The intake holes for H series case are really big enough for air to get inside. Comparing to older H series.