Originally Posted by
nk15
Interesting to see the different approaches taken by the major North American carriers.
I summarized the data in the AC forum, but it's worth reposting here.
AC & AA - purchased both options
Southwest - purchased disagree alert & separately installed AOA sensors.
WestJet - only disagree alert. No AOA sensors.
UA - did not select either 
From the linked article above:
A United spokesman said the airline does not include the features because its pilots use other data to fly the plane.
Yikes. That's not a good narrative. The Lion Air & Ethiopian pilots also used other data to fly their plane. What else did UA skimp out on? Nice to see AA taking a lead in safety, in this instance.