A bit confusing control layout
I tried it for a few days... GPS accuracy was pretty good (~1%), I found it a little bulky/uncomfortable for my narrow wrists. I also found the bezel controls to be non-intuitive as a first time GPS watch owner.
I ended up returning it and getting a Garmin 210 which I like a lot (the slightly slimmer, smaller face is noticeably more comfortable. The 210 controls are easier to figure out on the fly (admitted it took more key presses... but I felt that was an acceptable tradeoff). I found I didn't need all the fancy settings of the 410 workout programs.