On my home built Model A I used DOT 5 silicone brake fluid from the beginning. I have not had any problems with the braking system in the five years it has been on the road.
I am using a Mustang non-power master cylinder, GM front disc calipers with a Midland booster, GM drum rear, and have an adjustable proportioning valve in the rear line.
I will admit, it doesn't have the "throw you through the front windshield" feel that you get in a new car. Mostly because the Midland booster isn't doing much, running a prety high lift cam, there isn't much vacuum available.