Honestly, for me the most important things for GPS. 1) Consistency 2) Accurate pacing while running. While I do look at the GPS tracks when I 1st get a new device (or comparing devices), this isn't the be all or end all for the watch.Thanks for your thoughts on the 920 and Fenix.
How have you assessed the GPS Accuracy? My Ambit 2S seems to be about as accurate as I can tell. i.e. if I run an complicated out and back, the distance back is always the same as the distance out... at least to better than 1/10mi. Which means it's consistent. it may or may not mean it's 'accurate'. Ran a certified marathon course last month and it came up 26.3. Pretty close.
Happy to hear about the great stability. My experience with some gamins has been stable (310, edge 500) and others not very stable (405's). I truly want a Fenix3... but I'm not ready to be an early adopter. I want Garmin to work any bugs out on others first.
That being said, I've been looking at the GPS tracks of the 920xt in the satellite view at 20meters/inch. On suburban roads (about 10 meters wide) the 920xt has me running on the correct side of the road the entire time. Not only that, It usually shows the places that I've run on the sidewalk, through cross walks, and on the road. This has been very consistent. Yesterday I ran in the blizzard and it was still dead accurate and clearly showed the times I crossed the street to avoid plows.
Here are couple of examples:
Garmin Connect (yes, I started on the road and ended in the parking lot)
Garmin Connect (early with no traffic, so we were running in the middle of the road at times on the back streets)
Both of these were without GLONASS enabled. I've enabled GLONASS recently and find there's actually some improvement!
I can't imagine the fēnix3 will be worse seeing that they are using similar hardware and software. (Though I was fooled with the fēnix2)