I do.. I'm lazy enough that sometimes I'll keep my grip on the bottom, and double tap, even if I have to do it a few times. Happens when I still manage to do one handed activities.
Used it all day every day on an iPhone 6 Plus. Barely ever use it on the iPhone 6.
I actually miss it when I use my old 5s. I double tap to reach the far top corner and then forget the older iPhones don't have that feature. Then I have to wiggle my hand up the side like a barbarian.
It's OK when you only need to tap one thing in the upper portion of the screen. When you have to select multiple things one after the other, it's very tedious.