My first usage of Spice began in 1993. I had used Mentor's Accusim to design sampling holder and CRT driver and video amp. the accusim give me a 90% correlation with measured data. However It only run on the HP(allopo)workstation or Sun box. A HP workstation(Model 735: RISC CPU, with 32M RAM, 1G HD and 19" CRT) costs 32,000$.
So you can't always get it run anytime because there are other colleagues need to use it. In 1995, I first saw the PSPICE in an EDA exhibition and got a chance to test it.I found Pspice is smart enought and also give me the same correlation with measured data, but it can run on a cheaper 386 PC(4M RAM)! Late, I began to use Pspice instead of Accusim. So I think PSpice be welcomed due to it' nature running on the popularpc which every designer can have it, not the dedicated workstation. My another story is about layout tool. We also had acquried Mentor's MCM Station, but soon We migrated to Protel. Why this happened? The MCM Station' cost/performance was very bad!
Today There are less designers to use spice in thier daily work, especially in the board-level design. Becasue IC technology's advance, the main work of us is integrating ICs.
There is no need to run Spice again. Now most used tool is SI tool,but Spice not dead. There are much SI engineers to prefer use Hspice engine in SI analysis.