OK... i got my first US Air card on 12/6/2013 (instant approved for $17.5k) & wanted to get this before US Air/Barclays went away. Decided to pull the trigger even though it has only been 4 months and I have barely used the 1st card. (1x when I first got it for the initial spend and a couple of times this month because of the offer I just got) - Bottom line... I was instantly approved for $20k!!! 40K miles for me!!! Especially important since AA has now restructured their mileage rewards!!!
My first card is still open & I am using it.