As previously meantioned, the penultimate row (52BCHJ) is optimal if your not worrying about US immigration at places such as JFK or ORD. I read a report of someone in 52B who propped a bag up between the seat in front & the wall, put his feet on it, reclined into a flat bed position. I tried it out for myself flying to SEA (not really an immigration issue for UK peeps. Most pax were US) & it was brilliant except that my rollerbag didn't fit between the seats. I'd suggest a rucksack or softbag.

These seats have the added bonus of being first for service in the World Traveller/World Traveller Plus cabin since they start each end. Good for couples to.