[BlueTone]

I had a pilot tell me, as we were boarding, that the airlines are discriminating against tall passengers. I concur. I'm 6'8" and plan my route / time based on seat availability. There are some seats that I just don't fit in, my knees hit the seatback in front of me, my back against my seatback. I could fly the route without my butt touching the cushion.
Regarding the device, I personally wouldn't use it. I do wish the airlines acknowledged height as a factor in seat assignment. I usually have to pay more even tho I'm lifetime Gold with close to 2M miles.