New Horizons is slower than Voyager 1, and is also decelerating more. New Horizons will never pass the others. Voyager 1 is the fastest probe in an escape trajectory.
Anyway I'm still curious if V1 outlasts New Horizons
I read that one too.
Anyway, the Wikipedia article says:
After 2036, both [Voyager] probes will be out of range of the Deep Space Network.[14]
[The RTG] will decay too far to power the transmitters in the 2030s.