Dell S2721DGF 165Hz Very Fast Response Time UFO Test

IMPORTANT!! This is not captured using professional camera, therefore may not justify the same experience in real time.

Dell S2721DGF UFO Test
144Hz Fast -    • Dell S2721DGF 144Hz Fast Response Tim...  
144Hz Very Fast -    • Dell S2721DGF 144Hz Very Fast Respons...  
144Hz Extreme -    • Dell S2721DGF 144Hz Extreme Response ...  
165Hz Fast -    • Dell S2721DGF 165Hz Fast Response Tim...  
165Hz Very Fast -    • Dell S2721DGF 165Hz Very Fast Respons...  
165Hz Extreme -    • Dell S2721DGF 165Hz Extreme Response ...  

My sincere opinions:
1. Fast and Very Fast differences are not noticeable, Extreme seems to have overshoot.
2. In 144Hz, Fast seems to give better clarify, while in 165Hz very fast seems to give better clarify.