I'm not sure if I can tell the difference or if my brain is just tricking me into thinking I do (I guess I could answer that question with a double-blind test administered by a friend). What I can tell you is that I do NOT notice the difference in battery life. I switched from FHD to QHD about half a day after getting my S8+, and I was not able to notice a difference in battery life. Obviously there is some measurable drop in battery life. But it's clearly not enough that I notice it or that it disturbs my experience with the phone in any way.