The Plaza Premium is zoned with a noodle bar and various seating areas. As far as I could work out, the bar is pay! I must say I didn't ask specifically but I wasnt offered vouchers. Anyway, although they seem to have at least one shower there, I was sent to the Aerofresh shower area with a chit-its between the Amex and the United lounge. All good.
Given the drink situation noted above, I went directly back to the Amex Centurion lounge where I had some Mumm and prawn dumplings. Although it was moderately busy, I liked that they had staff wandering around offering refills