cadence analog flow tools
I ever used ic st@tion, quite easy to use, but IC5o are more powerful, and main chips that are successful are use the c@dence tools. So ic-st@tion although very cheap, still lack of evidence to work without serious consequences.
for lvs and drc, c@libre are very good tools, high speed, friendly interface, easy to debug, and again cheap. Again c@dence has a more powerful tool @ssura, which can do more than lvs and drc.
and for modelsim, it is just an simulation, designer will always use what they are used to.