I have used the MNS for about a year hiking in the mountains of Colorado. I decided I needed a GPS because I started climbing mountains without well-defined trails; I climbed the wrong mountain several times. I used the Brunton MNS in parallel with the Garmin Etrex Vista for about a month. The MNS is more accurate than advertised when finding positions. When entering a waypoint on the "way out" of a daylong hike, the MNS usually registered "found" within 5 feet of the landmark that I recrossed and recognised on the "way back." The MNS can acquire a signal in light forests near tree line, but not in the heavy forests of Ponderosa Pine at lower altitudes. The heavy smoke generated by the fire burning West of Colorado Springs this Summer killed satellite acquisition.
The altimeter is not accurate to within three feet, even given that the weather is clear and constant. It is of equivalent accuracy to my Sunto Vector altitude watch which is rated accurate to 10 feet; both must have the same internal mechanism. If I start climbing at 10,000 feet and climb to 14,000 feet, both devices will register about 13,900 feet. Interestingly enough, both devices always register low, which allows me to intuit the real altitude. On that closed loop between 10,000 and 14,000 feet, both mechanisms will register within 10 feet of 10,000 feet on return to the starting point.
The MNS mechanism is capable and has kept me from getting lost several times when weather on the return trip became bad.
The Tracklog function has little value because there is a very small limiting number of collected waypoints; a user is bound to miss that bend in the trail or special landmark that he would enter if he were setting waypoints manually.
The MNS is somewhat more accurate than the E-Trex Vista in finding positions. The E-Trex is far more user friendly in entering data. It might take twice as long to manually enter a route using the MNS vis-a-vis the E-trex.
I wear reading glasses. I cannot view the E-trex map or any of the displays without my glasses. I can view all the displays on the MNS without glasses. This was the ultimate reason I kept the MNS and returned the E-Trex Vista.
The Map on the Vista is so tiny as to be of little value. When I hike, I print a map of my route from my mapping software on plasticized paper; this printed map is far more convenient than the tiny map on the Vista.
