I personally find it rude to fully recline in any of the seats (International F, NGBC, and new 738 F excluded). Reclining a few inches seems reasonable, but the full recline is intrusive to the person behind you.

My favorite is the guys in F who fully recline almost immediately after take-off, then perch themselves up to eat the meal while leaving the seat fully reclined.

I'm sure there are plenty of opinions on someone's "right" to fully recline their seat, but I simply don't do it. I once ended up wearing an entire drink because my neighbor knocked it over while struggling to get out of his seat because the person in front had fully reclined.

It sometimes helps get the point across if you use the seatback (which is practically in your face) as a support to stand up and use the lav 2 or 3 times during the flight.