if you have two full-size carry-ons plus 10 personal items or tariff-free
shopping bags, the priority boarding is great.
If you are like me, just a median size backpack plus a laptopbag or
briefcase, not really useful.
Years ago, my previous flight delay, I had to rush to the gate at last
minute(the NRT young lady jogged with me and took me through elevator and
used first class passenger passage through security) At the gate, I saw some
people boarding latest, but they seemed important with several escort guys
in black suit. But of course they headed to first class cabin and I went to
econ class. So some people enjoy board last and exit first.