Navionics also details this on thier FAQ sheets:
http://www.navionics.com/MarineChartFAQs.asp?FAQID=17

What type of detail do your charts show?

Navionics charts show depth contours, spot soundings, navigational
aids, boat ramps, marinas, obstruction information such as reefs,
wrecks, and submergent and emergent vegetation.

Click here for examples of HotMaps.
Click here for examples of Classic and Gold Charts.

Luis Castro
Ft. Lauderdale, FL.

wrote:
I've got a Lowrance LMS320 and I've been thinking about buying some
of
these Navonics charts for it. Unfortunately, I would need the lakes
and coastline of Texas. That's 2 sets I think. $$

Anyway, my question is regarding the level of detail that these maps
provide. Are they simply electronic versions of the kinds of maps
that
I see at the sporting goods stores, Hotspots etc. or do they actually
provide a lot more detail than those paper maps have.? Underwater
structures, hazards, etc?

I suppose I could take my map in hand and go to a Marine store and
look
at demo of Navonics for the same area. Has someone done that or made
the comparison I'm asking about.

My feeling is that if all it is is a electronic version of what's on
paper then maybe its not really worth it. I can usually correlate
pretty well from the Mapcreate maps that I bought and other paper
maps.
Its a matter of information. If there is actually more information
in
the Navonics stuff then it may be worth it. I got a feeling that
I'll
always want paper anyway.

tks
Don