Not sure if this matters but there's also Pointshound which earns a decent rate into a select of FF programs (AAdvantage being one of them earning about 3x bonus). If you join through https://www.pointshound.com/expertflyer you get upgraded to tier 2 (~4x bonus) and a bonus 500 miles on the first booking. Not bad specially if your booking is under $350.
Plus I think you'll still get the AMEX 2x bonus.
Plus I think you'll still get the AMEX 2x bonus.