relatively new to the FF thing myself, but I made a conscious decision to go with AA/US over DL last year when I started flying regularly.
can layovers in general be a pain? yes. I've been rerouted a few times and got stuck earlier this yr in NYC due to weather. generally speaking though I've had a smooth ride, and the Plat line is usually very helpful. plus, all these segments is what will help me reach EXP this year.
AC isn't bad and the service inside does indeed make up for its appearance, and I love the fact that terminal T is right there past the North security checkpoint (which has its own TSA line), I only hope post merger the move the USAir gates to T as well.