At least in Western Europe, the big insurance companies are using mostly (Willis) Towers Watson's Moses (or are changing to Risk Agility FM) or Sungard's Prophe

At least in Western Europe, the big insurance companies are using mostly (Willis) Towers Watson's Moses (or are changing to Risk Agility FM) or Sungard's Prophet. License fees are very high and everyone is basically locked in, because the models get developed over many years. From my experience, the models aren't efficient. On one hand, the developers are very often actuaries without much understanding of efficient programming. On the other hand, the underlying software is old and doesn't take modern possibilities into account. So, instead of taking a big risk and developing a new software themselves, almost everybody is buying more physical machines for their hpc clusters.