A data storage device has multiple storage media surfaces and
corresponding heads, each storage media surface includes multiple
regions, and each head is for recording on and playback of information
from a corresponding storage media surface. A method of defining a
storage format for the storage media surfaces includes reading data from
each region on each storage media surface with the corresponding head,
measuring a record/playback performance of each head for each region on
each corresponding storage media surface based on the data read from the
regions, and selecting a track density for each region on each storage
media surface based on the measured record/playback performance of the
corresponding head for the region.