Mapping is not a Humminbird product.
If you got a 2010 issue Navionics, from what I have read, those have a less detailed mapping than previous issues.
I just got the 2009 issue a month ago and ordered that because of the above.
It seems that as the number of waters added with more HD versons, the less detail they had.
Which body of water are you concerned with? I'll check my version to see if it if different than yours. The 2009 issue is still available. You may have to attempt to purchase an older version for the details you want.
If interested, respond to my e-mail address
purdum43@aol.com