I have shot a couple of "tactical" matches. And for the matches I shoot, it is all about follow through and the timed second shot.
The reason I say this is, for the match I shoot, we have to engage each target twice. After the first shot, you have 10 seconds to run the action, correct for a miss, a fire again. We also usually have 5 targets per stage, and a total of 5 minutes to engage all 5. All targets are at varying ranges, and must be engaged in a preset order (vs. closest to furthest).
So my choice of barrel contour is going to be what ever you are comfortable with. Shorter, thicker barrels tend to be more repeatable. But not all calibers are as effective with "short" barrels.
Basically what I am saying is, it depends on the match you are shooting. The caliber you are shooting. And the ranges you are shooting...