Fenix 6X Sapphire - Problem with GPS Total Distance.

@ 9391586 - The issue isn't that they are not completely accurate.  Rather when compared to the prior Garmin models, the Fenix 6 doesn't seem to have an equal or better representation of the activity.  At least from my experience.

On my prior test, all 3 older Garmin devices were within .004 +-  of each other.  Using those figures, the 6X was .009 from its closest rival and .013 from the furthest.  Not much at all.  However, that suggests that the old Garmin devices are more consistent and possibly better equipped (As of now) to handle turns and tree cover than its newest model.

Another scenario could be, that not all Fenix 6 models are suffering from that problem.  

I'm pretty confident a firmware update can fix most if not all the issues.

@ Fnet -  Thank you for the information and graphs.  

As Jetguat said  "This is pretty disappointing" 

I'll try and remain optimistic and hope that Garmin's circuit design improved on its competitors by adding the necessary components to fix or lower the noise on the Sony Chip.

Perhaps the next firmware will remedy that problem.

I've had the same issues with mine, but mainly on the trails. Every 4 miles it seems to drop around 1/3 of a mile, which Garmin told me is acceptable... I'm sorry but a 900 dollar watch it should not do that. So it seems we are left to deal with it for the time being. It seems to be fine for cycling on the road though. Any suggestions would be helpful!

My 6X sapphire lost over a mile on a 14.5 mile run today

https://quantified-self.io/user/PlxFTqsLrOZdI7acfoZReZeg7q62/event/MfImhgLlyx1bR6CEGVmD

The Apex lost half a mile too. How do you know for sure that it's the Garmin that's wrong? There's so much tree cover that I can't tell where the trail actually is, and which device is staying the closest to it. How do we know the other two devices weren't going more off-course and causing them to measure longer distances?

You say it's a 14.5 mile run, but that's according to what?

Your conclusion might be correct, but it seems like you're just assuming the Garmin is the least accurate, without really knowing if it's the other 2 devices that were the least accurate. Without being able to measure the course on Google Earth because we can't exactly see it through the trees, there's not really any way of knowing what the correct distance is supposed to be. So if you don't know what the actual distance is supposed to be, I'm not sure how you can assume which device is measuring wrong.

GAIA, Movescount mapping, Strava route planning...all have that route somewhere around 14.25-14.5 miles.

Garmin vs GAIA generated route

https://quantified-self.io/user/PlxFTqsLrOZdI7acfoZReZeg7q62/event/bXXyyiHcuvJmQGUYYtYR

I’ve had similar but even more drastic issues. I’ve been has far off as 1.5 miles for a 17 mile run. I’ve worn both the Fenix 5 and the Fenix 6 on several occasions with very drastic differences in mileage. The 6 running dramatically shorter. I’ve also run with another runner on two of these runs wearing a Suunto 9 and they’ve been slightly shorter than the 5 but in comparison to the 6 but way higher/longer also. I’m not sure if it’s a Garmin update they can push but I hope they do. I have multiple .gpx tracks that compare the two watches. I’ve talked to a Garmin rep but they weren’t much help, but were pleasant and patient. The 6 seems to track poorly in cloudy skies and switchbacks. It almost seems to be excessively clipping distance in these situations. I have verified all setting for greatest accuracy but I am still coming up short on any run that is not a wide open road under a clear sky. 

But you're still no closer to determining which is correct. You need to accurately measure the course before you can comment on which one is the most accurate. If you run the same course with the F6 repeatedly, how much variation are you seeing? It's always difficult comparing different watches, especially those with different GPS chips. My experience tells me that the differences between the Sony chipset in the F6/945/Marq are no better or worse than the chips in the F5+/935/920/910 that preceded it. 

I know there are people who will say they expect better performance from the Sony chip, as well as others who say the opposite. However, the major improvement for the Sony over prior chipsets is energy use.

Same results.  I've been testing my F6 and older 920 on measured 7 and 11 mile trails.   On average, the F6 is up to 10% off while the older 920 is generally 2-3% short. 

In my opinion, no excuse a new and very much more expensive watch should be so much less accurate.

Running this morning and again the awful results of my F6 Titanium. For now, the watch is useless for running ... the bad thing is that the rest 70 percent of the features are pointless with wrong distace, time and pace.