Nostalgia-wise, SunOS (later Solaris) was my first peek at the 'real' computers which weren't what I was exposed to at home (Commodore/Amiga, Spectrum home comp

Nostalgia-wise, SunOS (later Solaris) was my first peek at the 'real' computers which weren't what I was exposed to at home (Commodore/Amiga, Spectrum home computers, occasional DOS). Likewise with IRIX. Also, as others have said - it was a good solid OS.