Similarly, I have both Amex Platinum and Delta Reserve. I asked a rep at the Atlanta Crown Room if I'd be allowed to bring 2 guests in on one card and 3 on the second card, if the situation ever arose. She said it was a tough question but probably open to interpretation. Said that she would allow it, as she'd treat each card individually but wouldn't be surprised if another attendant wouldn't permit it. Strangely enough, my 2nd Delta Reserve card is on its way, so let's see what they say about bringing in 8 guests. Lots of bachelor parties coming up...