Two observations:
1) I recently sat behind a gent in F who had been op-up'd (said he: "Wow, first class is really classy!"). The FA dutifully loaded him up on bloody mary's and not soon after, my seat was overwhelmed with noxious fumes that TSA should ban. So beware of not only seatmates, but those in front of you.
2) As a gag Christmas gift, I recently purchase some of these cushions for family members. They report they are surprisingly effective. The could probably fit in the front slot of most roll-a-boards for easy use during a flight.
(I have no financial stake in the above-named product)