When in doubt, do an experiment. I have a K-2006 too. Only difference I used a 10cc syringe to set the sample volume. With the 10cc sample I got 5.5 (11 drops), 25cc was 5.6 (28 drops). I would tend to believe the 25cc measurement because the sensitivity per drop is lower and the volume measurement is more accurate. Using the syringe both the 10 and 25cc levels in the test vial showed slightly above the marks on the vial. Nothing of significance.
Al