hm, i've been surveying on priority banking services for quite some time but decided to go with hsbc premier. they have a lot of privileges for premier customer, preferential rates (loans, currency ex), but of course currency ex you might be better off exchanging with the money changer out there in the market.
what appeal to me most with hsbc premier is their worldwide branches, of which they are willingly to help you to open account in anywhere in the world as long as they have branch there for free with no min balance. this is extremely useful if you are doing international business or probably thats why i dont have issue withdrawing money from paypal.
on top of that, hsbc can preapprove issuing you local credit card, of which you can get HKD (HK) credit card (no annual fee!) or US credit card, which allows you to purchase almost anything online. MY credit card is known to being blacklisted in some countries / major merchant. with that said, you save your currency loss if you are on the move all the time.
also, they have got this free wire transfer among HSBC accounts that allows you to move your money anytime, it took as lil as 5 mins for a wire transfer (TT) to move from any of my accounts, however, that's purely based on my experience despite they have claimed 12 - 48 hours. so basically if you need money urgently, you dont need western union

with home loan, i've checked that we could get BLR - 1.9%, thus far i've not gotten any offer better than that.
i doubt citigold / stanchart / any local regional priority banking supply you with all these global network