Just booked a KOA-OGG on Ohana. 5a and 5b are listed as Extra Comfort. When I selected them the drop down said $0, so I went for it. Got all the way through the process and after I paid, I got an error message that said "There was a problem processing your Extra Comfort seat request, please try again." However, my email confirmation says I have those seats. Of course, YMMV!