I have held an Amex charge card since 1990 and transferred to three different world offices in that time before I ended up in Australia. I can honestly say that the benefits of Centurion in Australia are perhaps the worst worldwide and represent poor value for money over a Platinum.
First year in Australia I moved my UK Centurion to here. Second year I explained that the levels of service and amenities were so poor in comparison to the UK and US I was comp'd a second year. I handed it back in year three and happily carry my platinum card.
I remain a stalward Amex customer and find it suits my lifestyle, but as to the Centurion card I guess I've been guilty of jumping on the ego polishing wagon at one time in my life, but frankly $4000 is a few very nice meals and on balance my palette always wins