This thread also reminded me to post that for all the people going nuts over the free beer machine at NRT, I was blown away by the MX lounges in MEX and ACA.
First of all, since everyone else is always alochol-driven, I'll start with the fact that there was a bartender for all your free drinks in MEX, but in ACA just a well-stocked self-serve bar to make 'em strong as you want 'em.
The clubs were quiet with very nice and attentive staff. The seats were comfortable, the design attractive, and the MEX lounge actually included a whole little gym. In short, nothing like RCC's at all, you really felt like a special passenger in there!
No problem whatsoever in gaining access to these lounges with MX ticket (bearing MP#, but plated by MX) and 1P card.
ETA: I was just reading recently on FT, along the same lines as PremEx's comments, that your particular *A airline doesn't matter for that day. IN fact, MX recommends using the Varig lounge (or another airline, SAS, maybe) at the LAX International terminal since there is no MX or UA lounge there.
[This message has been edited by robb (edited 11-22-2002).]