We visit the Delta lounge at MCO very regularly (we live here and fly often). Never a problem in that lounge so I wouldn't worry too much about American.
Didn't USAirways have a club? Did American take their gates after the merger? I had been in USAirways Clubs, got an occasional free pass when I was preferred level. Not really a big deal, I would not pay for it. They aren't free so I don't know why they would be like a schoolyard at recess. A one day pass for American is $50.