Bit of an old thread bump, but i noticed with some Amex cards there are complimentary lounge access. Do these apply to additional card holders or only the main cardholder?
Amex Platnium allow you free entry to lounges, including Centurion lounges for free with 1 guest (I think) on all Priority Pass lounges.
Gold Amex uses a different lounge scheme which is less than Priority Pass, and each entry is a fixed £20 per person, you can bring 2 guests I think. I have brought in 2 guests one time in T5. I used it on the way back in Dublin and took 1 guest in on Sunday.
Centurion Lounges are some of the best, Priority Pass is very hit and miss. The one in Tapei was brilliant, has a noodle bar, lots of free spirits. The one (there are 2 i think) in HK even has beer on tap that is self-served. Heathrow T5 and Dublin one is quite sad looking, although free alcohol is usually available. I tend to use it not so much as for the food and coffee, but a piece of mind and quiet. It’s just much more comfortable and I have no worry leaving my things on the seat and go get a drink or a snack.
p.s. when you look it up online, make sure you read the UK Amex reward, not the US, the US card comes with a lot more perks. This is because the fee Amex charges retailer are higher, therefore they are able to give back higher rewards to cardholders. Due to regulations in the UK, our fees are actually lower, and thus in return, the perks are not as good. For example, Amex Platinum in the UK you don't get all those Uber credits.