Brake friction technology is a constantly-evolving situation. In the middle-'50s, a Dallas, TX based string of brake shops touted their "Brakes with Brass" as being better than other brands. According to what's at allpar.com in Curtis Redgap's article on the '56 CHP police car tests, where a '56 Dodge with Chrysler-supplied metallic linings ran their tough brake tests and still stopped well (a rebuilder in Amarillo, TX was the supplier of those brake sets), then came the VelveTouch brake linings of the earlier 1960s which tested better than any other brand of brake shoes (if you can find that article, using a '60 Ford Galaxie for their test vehicle), you will also find pictures of failed brake shoes!), as metallic friction materials became more widely-used on high-speed-capable vehicles (i.e., 1961 Chevy Impala SS), although many drag racers put normal shoes on them so they could stage the cars (with cold brakes). The late '60s saw new FMVSS pedal pressure/deceleration rate specs OEMs had to meet. Metallic frictions, as "carbon graphite" frictions came online in the aftermarket. And now, the copper in the frictions is being deleted for water pollution issues, as ceramic frictions are becoming OEM in many cases. Ceramics tend to be more abrasive to the brake disc or drum, so GM started "cryogenic" treatment of their OEM brake items. As metallic were more abrasive than organics. Unless you've tried to keep up with these things, over the years, you get the best stuff the auto supply carries and go on down the road.
Where might things end up in another 20 years? Not sure, but possibly all of the remaining OEM NOS brake linings/frictions might have "shelf cured" and become harder with age, which might well affect their ultimate frictional characteristics to a certain extent.
Many of the better replacement brands have a "normal" product, an upgrade product, then a towing/hd/police vehicle product. As time progresses, though, the options we might have for our '60s+ cars will surely continue to decrease. Not being able to get the widest linings any more, for example, but the narrower ones. Either you find a reputable rebuilder (possibly an entity tied to a truck parts operation) and get your existing shoes re-done, or you deal with the local auto supply operatives. Some will be faced with a "brick wall" at the local auto supply as others will seek out other sources, by observation. OR you wave the magic plastic and UPS/FedEx brings them. Getting new brake drums can be worse!
So, good luck, y'all. Get the best brakes you can afford, from "somewhere". Drive Defensively and Responsibly.
Enjoy whenever necessary!
CBODY67