We usually get C+ because my wife is in a wheelchair (the disability desk will move her up if seating is available -- closer to the door, and the extra legroom makes the transfer to/from the aisle chair much easier and safer), including on our recent flight on a 330 (BOS-AMS). I don't think it would have been worth paying extra for.
(I DO wish we'd sprung for Premium Economy on the return flight on a 350 to DTW, but that's a different topic
)