Took the test and got a 0, but strange thing I noticed during the test was that "wiping" the cursor over the colored blocks during the test seemed to increase the saturation of the blocks, making the test much easier.
I noticed I had to spend a lot of time in the bottom two rows near the ends--in the purples, for instance, it was near-impossible for me to tell the last three tiles apart.
(Macbook Air, non-retina, Chrome 43.0.2357.134 (64-bit))