The GUI was fantastic. Minimal got out of your way as much as possible and used the hardware acceleration to great effect. IRIX 6.5 was rock solid, I used it as my main driver for years before switching to Linux, we also had some windows boxes floating around because we supported a windows binary but that and admin were the only things done on those, everything was either SGI or Linux. I was still using my SGI keyboard two years ago but it finally died.
