Dell s2209 has same panel like BenQ, Dell has better ASS
Model Response Time Panel
BenQ E2200HD 2ms G2G 21.5"WS AU Optronics TN Film (M215HW01 V0)
BenQ E2200HDA 2ms G2G 21.5"WS AU Optronics TN Film (M215HW01 V0)
Model Response Time Panel
Dell S2209W 5ms 21.5"WS AU Optronics TN Film (M215HW01 V0)
I think the 5 ms rt is an error 'coz the panels are exactly the same!