The last time that I was in Baltimore, I was told that there was a common club for (most) all airlines, that a PC card would work, but AMEX Plat. would not. Is my info out of date.
As for ticket and metal matching, I used NWs PHL WC with a NW ticketed codeshare on CO metal and an AMEX. Of course, the layout of some airports makes it impractical to mix and match.
Edited to clarify that it was a NW codeshare on CO metal.
[This message has been edited by 70Jaguar (edited 03-26-2003).]