No time to read all the comments, so this might be a duplicate.
I pay the rather exorbitant fee for an AMEX Platinum card. (I usually don't pay for colored plastic). Two essential features (plus one nice-to-have)
Essential: Worldwide access to a medical emergency number. I've used it twice, once in LA and once in Krakow. I talked to a paramedic both times, tho the second time he put me on hold and relayed info to a specialist. First one (LA) ordered a prescription from a nearby pharmacy. Second got me to hospital with English-speaking staff where they were able to take care of me (steroid shot for tendinitis in my foot, painful but not life threatening).
Essential #2. No credit limit. That SIN problem would have gone onto the card and we could have sorted it out at home. Imagine if access had been denied for a few days. The result would have been permanent vision impairment, all because of a paperwork problem. Not acceptable.
Nice to have: Access to CO/DL/AA clubs as part of membership.
Worth $350 or so, just for peace of mind (for both me and my wife.)