The user I replied to values battery life. iOS 26 has incurred a 15-20% penalty on the 16 series.
Performance is not as big of an issue anymore.
How the 17 will fare is a question mark, but repeated tests have shown that iOS 26 is so bad, so inefficient, that the 17 Pro Max on iOS 26 loses in repeated battery tests against both the 16 Plus and the 16 Pro Max on iOS 18. Which is ridiculous, as it has a larger battery. iOS 26 is, for the first time ever in iOS’ history, inefficient on the devices for which it is the original iOS version.
It might improve later, but if you value maximum battery life, updating a device to iOS 26 is not a good course of action. And for the second time ever, this applies to every iOS device, including the latest updatable version.
(As you know, the first instance of this was iOS 11).