Worse battery life than fenix?

The Instinct 2 has worse battery life when it comes to basic GPS when compared to the fenix 7. Instinct is only 30 hours and fenix 7 is 57 hours- that's practically double. This is why you are seeing a fall off in the battery. 

However, for just smartwatch use the Instinct 2 is rated for 28 days compared to 18 days on the fenix 7. This might be where the confusion is coming from. 

"Anything I’ve seen online says the battery on instinct 2 is much longer than the fenix but doesn’t seem to happen in practice and yes pulse ox etc off."

This was the reason I bought the 2X. As it turned out this is only the case if you don't use GPS very often or your workouts are very short. With Pulse OX off, but most accurate GPS option on, I only get about 4-7 days runtime. My bike buddy has a 7X which lasts longer in same conditions. 

That's why it is always a good idea to review the watch specifications before the purchase, not relying only on 3rd party reviews, which may be biased or wrong. The specs tell it rather clearly:

Perhaps the 2X specs might be better?  Trux?

Gonzo said:

Perhaps the 2X specs might be better?  Trux?

Sure, exactly. That's why I've compared Instinct 2 Standard & Instinct 2X Solar vs F7 Standard & F7X Solar 

You have to look at the specs for each watch. Instinct has a longer smartwatch life because it doesn’t have as big of a power draw. In gps modes (before solar), the Fenix will last longer because it has a larger battery. Once you add solar, things can flip flop back to the instinct. 

409c3a3d651e49e3bd7f51955bd2a889 said:

Once you add solar, things can flip flop back to the instinct. 

Not necessarily, click on the comparison table in my previous post. It compares both non-solar and X solar models too. F7X Solar still has longer battery life than I2X Solar in GPS mode in most modes, the exceptions are slightly longer battery life in some modes with permanent full solar support (which is rarely truly achievable). 

There's kind of an irony here.  An watch with amazing battery life, designed for the outdoors unless you use GPS which you use outdoors, then its not so great

5164992 said:

GPS which you use outdoors, then its not so great

It is still great and costs just ½ of the price of an F7