Overall, this watch is great. I've used it snow shoe camping, mountaineering, hiking, running, biking and bragging! ;)
Cons:
The GPS can take upwards of 5+ minutes to "Lock On" to the satellites. I usually put it on the "1 second fix" setting before turning on the GPS, then once it's locked on change it back to "1 minute fix" or "manual" depending on my activity. Once it's obtained an initial lock, subsequent locks seem to be faster.
Battery life on the 1 second fix setting is low, 6 hrs, just as advertised. But for most of my activities, the 1 minute or manual fix options provide plenty of battery life.
The watch offers a lot of features and as such there's a learning curve. Expect to spend a few hours playing with it.
The user manual could use some work...
The watch is not compatible with the mac version of TOPO!
You can't pull your track log directly from TOPO! (pc version). You have to pull the log using Trek Manager, export to a txt file, then import into TOPO!. This probably isn't the watches fault but instead TOPO!s.
Pros:
Once the GPS is locked on, it will track you anywhere. It works great in deep forest. It works great on the top of or in the shadows of mountains. It works in a car. It works in the city. I've never not had it work, except indoors, but then why would you use a GPS inside?
The navigation function for following pre-set routes and finding waypoints is great. Even better is the track back feature. It also provides quite a few in-flight statistics that are often helpful in estimating arrival time, duration, course error, etc.
I really like the sun rise, sun set feature. I wish this feature had an alarm, but since the watch has 3 alarm settings it's not too hard to manually set sun rise/set alarms. I wish it had tide and moon rise/set info as well.
The altimeter/barometer/temp work well, though i'm not a heavy user of these features but they serve my purposes fine.
Summary:
I really like this watch. But keep in mind it's a watch and cannot be expected to outperform handheld units. For me, using this in conjunction with a map & compass has worked out great as it helps provide that sanity check on position. I feel confident enough with this watch that I could navigate in a blizzard and make it back again. In fact, I did just that last week.