COS vs extension routing

Commercial Modules
2

Extension routing has a free trial.

EDIT: I would rather go with COS since it has more features, and what you are trying to do can be done with both modules.
https://wiki.freepbx.org/display/FPG/Extension+Routing-Admin+Guide

https://wiki.freepbx.org/display/FPG/Class+of+Service