Can't help myself.. I'm a tech-geek. As much as I like, and rely on low tech, I love to have high tech as backup.

To that end, I use a Suunto on all of my treks (as well as all of my training, running, MetCons and even when walking around). It's a pretty big watch due to the GPS antenna built into the main housing, but it has some great features that I have come to rely on. Altimeter, barometer, thermometer, elapse time, elevation gain, compass, current and average distance, as well as current and average heart rate though I don't use that when trekking. It's most useful feature is navigation. Routes can be created on a home computer and uploaded into the Ambit. I often drop waypoint pins in the route for water sources or crossings, potential camp sites and shelters, scenic features or key navigation points like turn-offs, or trail heads. Waypoints can be created on the fly as well and once saved and labeled, you can navigate back to them as needed. Routes can be run forward or backward. While using the Ambit for navigation, the watch can simultaneously record a bread-crumb trail of the track and record all the above data to be downloaded once back home in gpx format which can be saved and shared.

I also have a Core. The battery is pretty good, but it falls way short in the multi-use category when compared to many other units, especially the Ambit. And the display is notoriously difficult to see regardless of the light your in.