IF you want it for "offroad use" where no roads show up you
want one sold as a "Crossover" unit.
Personally Id rather have Two seperate units.
what are sold as "GPS" units aren't really.... sure they work off the satellites
but waypoint marks, tracing your route, etc are true "GPS" functions.
Most of the inexpensive units today are "Navigation units" which are GPS based, but they are "dumbed down" and are fixated on "highway & Road" navigation, where a true GPS simply takes tally of it's location, heading and altitude, though some can also show topo map screens.
But Like I said, I've got a highway navigation unit, a true GPS
one that does topo maps and Maidenhead Locator System
(
http://en.wikipedia.org/wiki/Maidenhead_Locator_System )
coordinates would be even nicer...
AD