I have used the Garmin GPSmap 76S for about a year and a half.
Great unit. It was designed as a marine use hand held. But I use it
for everything from driving to flying gliders. I am sure it will serve
me well in my new kayak. Also Gamin has been very good about supplying
firmware updates from there web-site support downloads page. when I
first started using the 76S
the firmware was version 2.0, I just installed firmware version 3.50
the other night. another thing that Garmin did for the 76s through the
firmware was to
upgrade the track log points from 2048 to 10,000 points. This was a
big plus to me as a soaring pilot for I convert the track log from the
76s with a program called GPSDump to a .igc file which I load into a
program call SeeYou, which lays the track log onto a 2 and 3D maps.
The 3D map even has a animation mode.
the increase to 10,000 point track log lets me set a most often
interval track line through the track log properties of the 76s which
draws a finer resolution line on the maps when loaded into the SeeYou
software. When I kayak through the Everglades this Christmas I will be
recording my track log for this very reason.
In my opinion The Garmin GPSmap 76S is one of the finest handheld GPS
devices you can find on the market.

Best Regards,
Carl