So the row 20 bulkhead is the preferred row for all equipment?
I've only done P+ once on a 788 domestic turn IAD-IAH-IAD but have little memory of whether I was in 20 or not (early morning groggy flights). Generally bulkheads in similar seating configs (row 1 of domestic F) can be annoying with not enough space to stretch legs (I'm tall), but those foot rests also get in the way in non-bulkheads.
I have a high-J 76U EWR-LHR daytime and then 764/76U LHR-IAD upcoming...