I'm on a Pro 2 now, but I was consistently getting 6+ hours. Now, it DOES depend on what you're doing. You can't, for example, edit video or watch movies or play high end games and expect to get 6+ hours of battery. But for writing in Word, checking email, light web browsing, writing notes in OneNote, that sort of thing--easy 6 hours, and sometimes more.
On Pro 2, using these settings has so far gotten me around 9 hours of actual usage. Again, doing heavier work changes that, so you do need to take that into account. Demanding tasks are called such for a reason, after all
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