Recently flew on a 77H in seat 26K. Another plus of the back row is that the plane usually fills from front to back. If the cabin is not full there's a good chance of having the seat next to or in front of you empty. I'm very sensitive to crowding and even in an extremely spacious and private J seat on the 77H having an empty seat around me increases my comfort. Another benefit of 26K is popping back to the lav in PEY, although if I do, i can sense the ire coming from the pax in PEY.