I have a different opinion and think the lounge at gate 108 is pretty meh. Both times I've been have been in the evening, before the departure of the ~9pm Hawaii flights. The lounge was quite crowded at these times. If you want a shower, good luck, the wait was several hours long. And the toilet facilities were filthy by Japanese standards. I think the most depressing thing is the lack of windows.

I've never been able to get into the TIAT lounge using PP because I've never been at Haneda between 1-5am...