I did not go to last U2 show in Dallas at AT&T Stadium, but if you are considering Dallas you may want to read this review of the acoustics. Particularly troubling are the high levels. Seems like GA and first level close to the stage would be good, but otherwise you might be rolling the dice. Most of the other stadiums are open air, except Houston which also has a retractable roof.
I'm considering going elsewhere where acoustics will not be a challenge personally...fingers crossed.