Oh, I just remembered that the minrad and maxrad setting can be automated. Simply set them to "0".

This pic is not the 16000 ray setting, but a 4000 with min- maxrad settings to "0".

Um, it looks nice, and renders a bit faster I think. Now I'm puzzled .

RESULT:
The shading is different here. The diffuse is more smoothed out! Can you see it, compared to the former pic with 4000 finalgather rays?