Free forever, and you may still not be allowed to use it
Most simulation vendors publish a free edition that never expires. The caps are the wrong thing to compare. What separates them is whether the license permits the work you were planning to do.
Simulation
Simio alternatives
Everything we have published that puts Simio beside another product. Nothing here is written for this page: each piece is a full assessment in its own right.
Before you compare
Simio scores highest on modeling capability, at 17 of 20. An object based approach the published material presents as extensible inside the product, with three dimensional modeling and a documented scheduling layer built on the same engine. Discrete event centered, with agent style behavior described in positioning terms rather than as a documented separate paradigm, so the multimethod question reads as not stated rather than as a yes.
The same rule on every page in this section: the criterion this product scores highest on, and whether that score leads the assessed field.