American Express Membership Rewards - Amex international lounge access

Hi. I have a US Amex platinum. I know that the UK plats get airport lounge access via priority pass. Has anyone tried to use the US platinum to get into non-Delta, Continental, or Northwest international lounges? Are UK platinum cards distinguishable from US ones? Do the UK plats show the priority pass and their Amex or is either one sufficient to gain access? Thanks!

You need to show the Priority Pass. The lounge staff will want to take an imprint of the Priority Pass (to handle billing for guests, etc.) and could care less about the Amex.