Answers varied a great deal based on the perceived intrusiveness of the question, but one pattern became clear: it was possible to get more people to answer that they had engaged in a given behavior if their own behavior was approached indirectly.
Most of our quantitative questions were banded by orders of magnitude, to make it as simple as possible for the respondents to answer: The respondent could choose one of a number of bands, from 10-100 IOPS, or 101-1, 000 IOPS, etc.