David,

I have both an Etrex Legend and a GPS72 (like the 76 without mapping capability). We will be carrying both in the Tybee500. Both will be loaded with the same waypoint navigational data. The smaller legend will be stored on person in a pocket in a dry bag for reference where close navigation or specific information is needed. The 72 will be mounted to the boom or mast and fixed to display heading and speed information since it has such a large display and can be read from a distance.

Regarding the buttons - the 72 / 76 is MUCH easier to use through a dry bag. The joystick on my legends (I've had two) has been a little problematic and even without being inside a drybag it's not easy to manuever.

I like both units for different reasons, however, if I were looking for one to do it all, I would go with the 76.