The Garmin Forerunner series is a range of devices designed for running. Specifications vary across the range, some are simple watches, others have more navigation features. None of them support mapping.
Note the Forerunner 50, 60 and 70 do not use GPS, they only work with a heart rate monitor, footpod or bike speed/cadence sensor.
Forerunner 201 / 301
|Garmin Forerunner 201|
|GNSS||12 channels (waas;egnos)|
|Memory||Flash: no . External: ? no.|
Older model, poor performance. Probably best avoided for OSM-usage. Compatible with GPSbabel. The 301 model comes with a breast strap for heart rate monitoring, otherwise the units are identical.
Forerunner 305 / 205
|Garmin Forerunner 205|
|GNSS||12 channels, SiRFstar III (waas;egnos)|
|Memory||Flash: no (13000 max logging). External: ? no.|
|Batteries||internal Li-Ion (10hrs lifetime)|
The Forerunner 205/305 fix many of the bugs and design flaws that plagued the 301. The unit uses the new SiRFstar III chip-set and positions the antenna better. It maintains satellite lock without problems in dense forests and built-up areas. The 305 differs from the 205 in the HR chest strap and support for an optional cadence monitor. The unit comes with a built-in Li-Ion battery that lasts around 10 hours between recharges. It connects via USB and comes with Garmin Training Center (Windows) which allows saving workouts in tcx format. It's also supported by gpsbabel and garmintools allowing readout of tracks in gpx-format. The "lap" button can function as a quick "waypoint" recorder but the device also supports proper waypoints (max. 100) via "mark location" in the navigation menu. The most significant limitation is the internal memory supporting only 13000 trackpoints which corresponds to 3,5 hours of recording in 1/sec mode.
At end of year 2009 it seems Garmin no longer markets Foreunner 205, the new equivalent seems to be Forerunner 405
Comparison to eTrex HCx
In direct comparison to the eTrex Vista HCx I've observed that the Forerunner 305 often performs better, i.e. has a much better accuracy.