How is the firmware stability lately? How reliable are gps and altimeter?

Good question...nobody here?

I want a reliable watch for a 100 miler and don't want crashes and loose route, data...

Breadcrumb route is enough for me.

Only used up to 28 miles in a single run.

However no crashes ever APART from when I attempt to use Pace Pro on a course for an ultra level distance. Then it restarts.

No problem loading and following any course (inc the Arc , which I loaded to check but havent raced).

GPS is great as is battery of course 

Altimeter 'seems' fine providing you calibrate before an activity (IE no weird spikes).

All the above is in ref to the 2x incidentally.

The 2s has significantly less battery and the GPS is not as good. Plus the screen size is tiny.

No matter what size your wrist I would strongly recommend going for the 2x.

If you feel it's too big maybe go for the Coros Pace 3 or the new Garmin 165 which both have bigger screens than the 2s.

Wow does Instinct 2 series support Pace Pro? Seems the specs on the official site show no support.

Ultrawalker said:

I want a reliable watch for a 100 miler

It may depend how long you need for the 100 miles. The 2S model offers up to 22 hours in GPS mode (little bit more with solar support, but it cannot be relied on, and especially not continuously). At the standard I2 it is 30 hours, and 60 hours at I2X. Those are theoretical max values in ideal conditions, and I would not rely on them.

You have the possibility to use the Max Battery GPS mode using the UltraTrac feature, recording the GPS track once a minute. It increases the battery life little bit more than twice. And finally you can use the Expedition mode, recording some data every 60 min (resp. the period is configurable between 15 and 90 minutes), where  the battery life increases to multiple days or even weeks, but the recorded set of data is minimal.

I recommend doing some tests with the UltraTrac and Expedition modes before doing the big run. First of all, the tracker needs to be calibrated in order to record the distance properly (or at least approximately) even without the GPS. And then to see whether the recorded data meets you expectations. And also to see how quick the battery drains in real conditions (and not just in a lab test).

Personally I have no problems with the stability of the firmware (currently using beta v15.02), and experience no crashes, but I never tried an activity of similar length or duration.

Anyway, if the results are important to you, I definitely recommend double or triple recording the run on multiple devices. When nothing else, then minimally on a phone (for example with the Strava app). You will likely need a power bank for that, with most phones, though.

Please note that if you connect the watch to a charger, the activity will be stopped and saved. Splitting the activity into smaller parts may be wiser anyway. You can always merge the parts together with an external tool such as the FIT File Tools

100% the 2x

anonymous16 said:

Wow does Instinct 2 series support Pace Pro? Seems the specs on the official site show no support.

I do not know why it is not in the specs, but all I2 models have the PacePro feature.

Instinct 2 Series Owner's Manual - PacePro Training (garmin.com)

If you change USB Mode in System from Mass Storage to Garmin it doesn't interrupt the activity

I don't recommend Ultratrac at all. I was able to have a Fenix 6X Pro Solar during 32 hours on a 100 miller with everything enabled and using maps all time. The Instinct 2X should last more and you can allways disable bluetooth, do not use LiveTrack and use the Only GPS mode (which should be enough).

Have a look at this video for some tips: https://www.youtube.com/watch?v=8qM58s_MaMg . He is using a 955 in fact.

Problem I see is there's no documentation or nobody tested the watch running so long and the 2X has had some firmware issues (like the waypoint limit and the 166km limitation). I'm also interested in the report while navigating before I try to do it on summer.

dreamer_ said:

The Instinct 2X should last more

Instinct 2X has the same specs as Fenix 6X - up to 60 hours in GPS mode. However the OP was asking about Instinct 2S, which only offers up to 22 hours in GPS mode.

What Garmin says in the specs is not accurate. Let me explain.

The Instinct 2X does not have mapping. What I saw in the Fenix 6X Pro Solar is that when you are using maps, the battery drains a lot faster than what is told in the specs.

My watch lasted only 32 hours even with solar charging during many hours, which is a lot less than the 60 hours. That mapping screen consumes battery. It is better to switch between screens but not use maps all time. This seems pretty obvious but I didn't know that in that 100 miller course. Basically I run thinking that 60 hours was a lot. The Instinct 2X does not plow all that info and does not need to refresh it. You are using just the old line and the arrow.

Instinct 2X has a lot more duration using the Solar charge than the Fenix 6X Pro Solar. The battery of the Instinct 2X should last a lot more during your race for these 2 reasons.