When you have compared all of the phones with ALL combinations of use, then come back and show us. 10 hours of use for you will be far different from 10 hours of use for me. Playing video or looking at pictures will be far different to looking at text messages. Every individual is different, and while I accept a variance in battery quality, when it comes down to it, the rate and frequency at which people charge their phones, and how they use their phones will have a far greater impact on battery life. Some will find their plus is better, some the X better. Both are right. If you want to be pedantic, the iPhone X has, FACT, a bigger batter than the 8 plus, but not the 7 plus.