I've used barcons for decades on three of my bikes - one ratchet friction, two indexed. Two Suntours and a Shimano.
My
recumbent has used friction barcons since the early 1980s. The barcons sit just outside the grips on the long-wheelbase high-rise handlebar, and make it easy to double-shift the half-step + granny drivetrain (was a 14-38 in the back for a while, now a ramped 14-32).
My racing bike (
Raleigh Pro Mk IV) lost its drop bars as soon as I let my Cat 4 license lapse in the 80s, and after some experimentation I settled on Scott AT-2 bullhorns, with Suntour 7-speed barcons in the ends. Easy to reach and reliable. After a barcon came loose on a very steep ride last month, I decided to try to switch to 7-speed RSX brifters, but switched back to the barcons in a jiffy. I'll probably put narrower bullhorns on the racer - I tried Nitto Aerodynamics, but the long curve makes them look like "DUI bars". I'll get something with just a little sweep like the AT-2s but narrower.
I knew I'd be busy when I'm captaining our
tandem, so I installed Shimano 7-speed barcons in short bar ends, and it's been reasonably trouble-free for thousands of miles.
Those two bikes of yours look great. I just re-donated two barcon-bearing drop bar bikes from the same era as yours to the local
Rusty Spoke bicycle collective on behalf of another bike charity that couldn't use them, and they were well-received. Hope they find good owners.