I have the 55ec9300 and I have no issues with my set minus some very slight stutter on scrolling news tickers. I was at the VE shootout and although the JS9500 and the 940c looked great, they still do not have the wow factor that the OLED can deliver.
I was on this forum almost everyday searching for something better . Since Ive had this set It has hardly crossed my mind to replace it, and sad to say Ive been a ghost around here. Maybe when the 4k Blu Rays are released ill upgrade .
To the original OP , you must have received either a bad set, had settings completely muffed, or some terrible source material. Its just not possible for the OLED to look worse than the other model you mentioned.