At the end of SGI's first life, PC hardware was running rings around Irix workstations. The O2 was basically the slowest machine you could buy at the time. Where I was working at the time we switched our PRO/Engineer machines from SGI to whitebox PCs as soon as PTC ported to Windows NT. A dual-CPU Pentium Pro with Fire GL Pro absolutely smoked the O2 and Indy machines it replaced. So that was my experience, a shop that bought SGIs as long as they were the best platform for a particular software package, and threw them out at the earliest opportunity.