My first experiences were several, all in 1979-1985 at Purdue University:
PDP11/70 running version 7
PDP11/45 running version 6
PDP11/40 running version 6
VAX 11/780 running 4.1 BSD
VAX 11/780 dual CPU (originally developed at Purdue) running a hacked dual/slave version
of BSD
(don't recall if it was 4.1 or 4.2 at that point)
VAX 11/750 running 2.9 and later 2.10