I blew a front wheel cylinder in my '64 twice, it is a fun experience to not have brakes when you expect to have brakes
Make sure you have a good operating e-brake because you will need it eventually 
I spent the most time on my rebuild addressing brakes over almost everything else so now I have disc brakes on all four corners which seems like overkill on a sub 3200 pound car and a inline six but I never want to experience brake failure again, made it twice with no mishaps I figure the odds are growing against me now
IMO a single master is questionable on a brand new brake system (my issue was drums that had been turned too many times, new shoes it worked fine but as soon as the shoes got enough wear out popped the wheel cylinders (took twice to figure out what was happening) I fixed it by installing new drums (if someone was close and was interested in a set of never turned front drums for a six cylinder hit me up I might give you deal you can't refuse) I guess I am saying that every component has to be operating correctly to avoid brake loss, it doesn't have to be just new brake lines but shoes, drums, etc any single failure will result in zero brakes and you have to fall back to the e-brake, just try to stop a car with just the e-brake from 35MPH, if you have a manual transmission you can downshift to slow yourself down some, if you are thinking & not in a panic and you have the room to stop before ramming the car in front of you or running over the little kid that rode his bike out in front of you.
So yes I think brakes are maybe the most important things to have right and operation with as much redundancy as you can put in there and a single MC is single point of failure, I am not saying people didn't drive around for a long time with just single MC and were fine but IMO unless you are restoring a car back to original for show or a museum I would concentrate on upgrading the brakes, IMO.
See Ya,
Mike
I just hope those are not as hard to get off as a '64 trunk lock 
