By Murphy's Pack
Three GPSr units are compared here, the Garmin Vista was added when a friend offered his Vista for testing. I own the Magellan units, so this comparison is from a Magellan point of view. The two Magellan units are toward the lower end of the Magellan line while the Vista is toward the high end of the Garmin units. The Vista has compass and altimeter while the Magellan units lack both. The SporTrak Map sold for $140 in April 2005, the 210 for $137 in June 2006 and the Vista for $300 in 2000.
Observation:
One aspect missing from all these GPSr units is a programming interface such that programmers could create their own applications for these units. They could be more specialized for specific applications, like a better GeoCache manager with more info on caches or a better search for cache names or a way to delete found caches. If such applications were available, the manufactures could sell more units; maybe not enough to justify the companies building the applications themselves but enough for open source people to build for their own interests. This seems like a real opportunity for some GPS company.