Two questions:

1) For a shotgun-speclalized Courier choosing between Fast Shot and Trigger Discipline, which of the two is preferable?

Fast Shot means more shots fired per unit of time, meaning more DPS and higher chance of triggering And Stay Back, but lower accuracy per shot and shorter engagement range. However, higher spread might also be an advantage when shooting at fast, erratically moving targets such as Cazadors. Accuracy loss can be partially compensated for with VATS perks or Steady. The downside of that, in turn, is Steady addiction and dependence on supply. However, after Dead Money, you get an infinite supply of Steady, and Logan's Loophole or perks can be used to minimize the chance of addiction.

Trigger Discipline means fewer shots per unit of time, but greater accuracy and engagement range. With the right choice of perks, accuracy and engagement range in VATS can be vastly increased, while the loss of speed and increased AP cost may be mitigated with perks, non-addictive +AP foods and plentiful chems from the Jet family.

2) How do I find out the AP cost of reloading a weapon in VATS? The wikia publishes the AP cost of attacks, but never of reloads.