The Feel Between Manual and Power Brakes

TrailBeast said
All you should really notice is just a bit more resistance at the first part of the pedal travel.
Maybe just a hair more pressure needed on the brake pedal.
If done right, you shouldn't notice much difference overall.

This post is spot on.

Power assist in the braking system of an a-body gives you next to nothing but takes away from you:

Under-hood space
Brake feel
Adds another potential failure point