Greg et al:
I used those 1/8" cable clamps on a driving brake just once on my first Dune Buggy. They lasted about three pulls and then started to slip.
I listened to my brother and brazed the overlapped cable ends together, and that lasted about one season. Then, I made up what amounted to the same ends that CB and Kymko sells today: A threaded end with a larger shaft at the bottom of it with a hole inside to accept the cable. There is a set screw on the outside that gets screwed in to pinch the cable and, Voila! I have never had one pull out, even with my muscular son driving.
Other people have told me they use the clamps, especially on clutch cables (and I have too) with good results, but there seems to be a lot more pulling force on the E-brake cables and I've not found the cable clamps to be that reliable there.
gn