On my last Global First trip on a 747 I was in 2K and I had a really hard time getting my 21" carry-on into the bin right above my seat, so I choose 3K for my next trip. For the trip after that I'm traveling with a friend so I choose 1A/K for us. I have no idea where we're going to put our stuff on that trip, although I do see on
SeatGuru that there is storage space between 1A and 1K and also right in front of 3C and 3H.